feat(path-picker): show hidden files and folders, and harden the secret blocklist

The picker behind Link Existing's "Browse" and the mobile keyboard's Path key
refused every path with a dot-prefixed segment, so `.github/workflows/ci.yml`
could not be selected and a hidden folder could not be opened at all. It gains
the same `.*` toggle as the File Viewer: default OFF, per-device, and applied to
both the listing and the preview endpoint, which re-resolves the path
independently.

That dotfile filter was quietly doing security work. The picker's roots include
Home, so with every hidden path unreachable the shared blocklist never had to
name the credentials that live in dot-directories. Lifting the filter removes
that accident, so `isSensitivePath` now covers them explicitly: SSH keys at any
depth rather than only under $HOME, GPG keyrings, AWS/GCloud/Azure/Docker/
Kubernetes credentials, npm, Yarn, git, gh, netrc, PyPI, RubyGems, Cargo and
Terraform tokens, .pgpass and .my.cnf, and the Claude and Codeman agent
credentials. `~/.codeman/` and `~/.claude/` stay attachable as trees, since the
publish skill and the review-card loop read from them; only their secret-bearing
members are named.

Everything else still applies with the toggle on: blocked trees, sensitive
files, root confinement, ownership scoping and symlink-escape checks. A hidden
entry whose realpath is a secret is dropped from the listing, and opening it is
refused.

Follows #221

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

src/web/public/keyboard-accessory.js

@@ -33,6 +33,12 @@
 // Shared Filesystem Path Picker
 // ═══════════════════════════════════════════════════════════════
 
+// Per-device, and deliberately its own key rather than a shared "show hidden"
+// preference with the File Viewer: that tree is confined to one workspace, while
+// the picker browses Home and every configured root, so wanting dotfiles in a
+// project does not imply wanting them in ~.
+const PATH_PICKER_SHOW_HIDDEN_KEY = 'codeman:pathPickerShowHidden';
+
 const PathPicker = {
   overlay: null,
   _options: null,
@@ -43,6 +49,7 @@ const PathPicker = {
   _previewOverlay: null,
   _previewRequestSequence: 0,
   _previewPreviousFocus: null,
+  _showHidden: false,
 
   /**
    * Open the lazy filesystem browser.
@@ -53,6 +60,7 @@ const PathPicker = {
     this.close(false);
     this._options = options;
     this._selectedPath = '';
+    this._showHidden = this._loadShowHidden();
     this._previousFocus = document.activeElement;
     this._previousFocus?.blur?.();
 
@@ -74,6 +82,7 @@ const PathPicker = {
         <div class="path-picker-nav">
           <button type="button" class="path-picker-up" title="Parent folder" aria-label="Parent folder">&#x2191;</button>
           <div class="path-picker-current" title="Current folder"></div>
+          <button type="button" class="path-picker-hidden" title="Show hidden files and folders" aria-label="Show hidden files and folders" aria-pressed="false">.*</button>
           <button type="button" class="path-picker-refresh" title="Refresh" aria-label="Refresh">&#x21BB;</button>
         </div>
         <div class="path-picker-status" aria-live="polite">Loading...</div>
@@ -100,6 +109,8 @@ const PathPicker = {
       if (current) this.select(current);
     });
     overlay.querySelector('.path-picker-refresh').addEventListener('click', () => this.load());
+    overlay.querySelector('.path-picker-hidden').addEventListener('click', () => this.toggleHidden());
+    this._syncHiddenButton();
     overlay.querySelector('.path-picker-up').addEventListener('click', () => {
       const parent = overlay.querySelector('.path-picker-up').dataset.parent;
       if (parent) this.load(parent);
@@ -120,6 +131,38 @@ const PathPicker = {
     this.load(options.initialPath || '');
   },
 
+  _loadShowHidden() {
+    try {
+      return localStorage.getItem(PATH_PICKER_SHOW_HIDDEN_KEY) === '1';
+    } catch {
+      return false;
+    }
+  },
+
+  _syncHiddenButton() {
+    const btn = this.overlay?.querySelector('.path-picker-hidden');
+    if (!btn) return;
+    const label = this._showHidden ? 'Hide hidden files and folders' : 'Show hidden files and folders';
+    btn.classList.toggle('active', this._showHidden);
+    btn.setAttribute('aria-pressed', this._showHidden ? 'true' : 'false');
+    btn.setAttribute('title', label);
+    btn.setAttribute('aria-label', label);
+  },
+
+  toggleHidden() {
+    if (!this.overlay) return;
+    this._showHidden = !this._showHidden;
+    try {
+      localStorage.setItem(PATH_PICKER_SHOW_HIDDEN_KEY, this._showHidden ? '1' : '0');
+    } catch {}
+    this._syncHiddenButton();
+    // Reload where we are rather than resetting to the root. Turning the toggle
+    // OFF inside a hidden folder makes the current path unbrowsable again; the
+    // server answers 403 and load()'s catch falls back to the default root,
+    // which is the only place left to stand.
+    this.load(this.overlay.querySelector('.path-picker-current').textContent || '');
+  },
+
   async load(path) {
     if (!this.overlay || !this._options) return;
     const loadSequence = ++this._loadSequence;
@@ -131,6 +174,7 @@ const PathPicker = {
     const params = new URLSearchParams();
     if (path) params.set('path', path);
     if (this._options.sessionId) params.set('sessionId', this._options.sessionId);
+    if (this._showHidden) params.set('showHidden', 'true');
     try {
       const response = await fetch(`/api/filesystem/browse?${params.toString()}`);
       const result = await response.json();
@@ -248,6 +292,9 @@ const PathPicker = {
     const requestSequence = ++this._previewRequestSequence;
     const params = new URLSearchParams({ path: entry.path });
     if (this._options?.sessionId) params.set('sessionId', this._options.sessionId);
+    // A hidden file is only reachable while the toggle is on, and the preview
+    // endpoint re-resolves the path independently, so it needs the flag too.
+    if (this._showHidden) params.set('showHidden', 'true');
     const previewUrl = `/api/filesystem/preview?${params.toString()}`;
 
     const overlay = document.createElement('div');

src/web/public/styles.css

@@ -11980,7 +11980,8 @@ body.touch-device.cjk-input-visible .main {
 }
 
 .path-picker-up,
-.path-picker-refresh {
+.path-picker-refresh,
+.path-picker-hidden {
   flex: 0 0 38px;
   height: 38px;
   color: var(--text);
@@ -11990,6 +11991,20 @@ body.touch-device.cjk-input-visible .main {
   cursor: pointer;
 }
 
+/* Show-hidden toggle: a literal `.*` glyph rather than an icon, so its meaning
+ * (dot-prefixed files and folders) survives every skin and font stack. */
+.path-picker-hidden {
+  font-family: var(--font-mono, monospace);
+  font-size: 0.9rem;
+  font-weight: 700;
+  letter-spacing: -0.05em;
+}
+
+.path-picker-hidden.active {
+  color: var(--accent);
+  border-color: var(--accent);
+}
+
 .path-picker-up:disabled {
   opacity: 0.35;
   cursor: default;

src/web/routes/file-routes.ts

@@ -315,11 +315,25 @@ function findMatchingPickerRoot(roots: FilesystemBrowseRoot[], candidate: string
     .sort((a, b) => b.path.length - a.path.length)[0];
 }
 
+/**
+ * Whether a path has a dot-prefixed segment anywhere below its browse root.
+ *
+ * Checked against the REALPATH, so a plainly-named symlink pointing into a
+ * hidden tree is caught too. Callers skip it when the request opts into hidden
+ * entries (`showHidden`), which is why the sensitive-path blocklist and the
+ * blocked-tree checks must stand on their own: with the toggle on, this is no
+ * longer the thing keeping `~/.config/gh/hosts.yml` out of reach.
+ */
 function containsHiddenPickerSegment(root: string, candidate: string): boolean {
   const rel = relative(root, candidate);
   return rel !== '' && rel.split(sep).some((segment) => segment.startsWith('.'));
 }
 
+/** Parses the picker's opt-in `showHidden` query flag (absent means off). */
+function wantsHiddenPickerEntries(showHidden?: string): boolean {
+  return showHidden === 'true';
+}
+
 function getFilesystemPreviewKind(fileName: string): FilesystemPreviewKind | undefined {
   const extension = extname(fileName).slice(1).toLowerCase();
   if (FILESYSTEM_IMAGE_PREVIEW_EXTENSIONS.has(extension)) return 'image';
@@ -431,7 +445,8 @@ async function resolveFilesystemPickerPath(
   ctx: SessionPort & ConfigPort,
   req: FastifyRequest,
   requestedPath: string | undefined,
-  sessionId?: string
+  sessionId?: string,
+  showHidden = false
 ): Promise<ResolvedFilesystemPickerPath> {
   const roots = await resolveFilesystemPickerRoots(ctx, req, sessionId);
   if (roots.length === 0) {
@@ -453,7 +468,7 @@ async function resolveFilesystemPickerPath(
   if (!matchingRoot) {
     throwFilesystemPickerError(403, ApiErrorCode.INVALID_INPUT, 'Path is outside the allowed browse roots');
   }
-  if (containsHiddenPickerSegment(matchingRoot.path, resolvedPath)) {
+  if (!showHidden && containsHiddenPickerSegment(matchingRoot.path, resolvedPath)) {
     throwFilesystemPickerError(403, ApiErrorCode.INVALID_INPUT, 'Hidden paths are not available in the file picker');
   }
 
@@ -662,12 +677,14 @@ function inheritedHeaders(reply: {
 export function registerFileRoutes(app: FastifyInstance, ctx: SessionPort & EventPort & ConfigPort): void {
   // Lazy filesystem listing for the Link Existing and mobile input path pickers.
   app.get('/api/filesystem/browse', async (req, reply): Promise<ApiResponse<FilesystemBrowseData>> => {
-    const { path: requestedPath, sessionId } = parseBody(FilesystemBrowseQuerySchema, req.query);
+    const { path: requestedPath, sessionId, showHidden } = parseBody(FilesystemBrowseQuerySchema, req.query);
+    const includeHidden = wantsHiddenPickerEntries(showHidden);
     const { candidatePath, resolvedPath, roots, matchingRoot, blockedTrees } = await resolveFilesystemPickerPath(
       ctx,
       req,
       requestedPath,
-      sessionId
+      sessionId,
+      includeHidden
     );
 
     if (isBlockedPickerPath(resolvedPath, blockedTrees, true)) {
@@ -703,7 +720,7 @@ export function registerFileRoutes(app: FastifyInstance, ctx: SessionPort & Even
     const entries: FilesystemBrowseEntry[] = [];
     let truncated = false;
     for (const entry of dirEntries) {
-      if (entry.name.startsWith('.')) continue;
+      if (!includeHidden && entry.name.startsWith('.')) continue;
       if (entries.length >= FILESYSTEM_PICKER_ENTRY_LIMIT) {
         truncated = true;
         break;
@@ -718,7 +735,8 @@ export function registerFileRoutes(app: FastifyInstance, ctx: SessionPort & Even
       }
 
       const targetRoot = findMatchingPickerRoot(roots, targetPath);
-      if (!targetRoot || containsHiddenPickerSegment(targetRoot.path, targetPath)) continue;
+      if (!targetRoot) continue;
+      if (!includeHidden && containsHiddenPickerSegment(targetRoot.path, targetPath)) continue;
 
       let type: FilesystemBrowseEntry['type'];
       let size: number | undefined;
@@ -783,12 +801,13 @@ export function registerFileRoutes(app: FastifyInstance, ctx: SessionPort & Even
 
   // Inline preview for files selected through the root-confined filesystem picker.
   app.get('/api/filesystem/preview', { compress: false }, async (req, reply): Promise<void> => {
-    const { path: requestedPath, sessionId } = parseBody(FilesystemPreviewQuerySchema, req.query);
+    const { path: requestedPath, sessionId, showHidden } = parseBody(FilesystemPreviewQuerySchema, req.query);
     const { candidatePath, resolvedPath, blockedTrees } = await resolveFilesystemPickerPath(
       ctx,
       req,
       requestedPath,
-      sessionId
+      sessionId,
+      wantsHiddenPickerEntries(showHidden)
     );
     if (isBlockedPickerPath(resolvedPath, blockedTrees)) {
       throwFilesystemPickerError(403, ApiErrorCode.INVALID_INPUT, 'Access to this file is blocked');

src/web/schemas.ts

@@ -65,6 +65,14 @@ const filesystemPickerPathSchema = z
   })
   .refine((p) => !p.split('/').includes('..'), { message: 'Path traversal is not allowed' });
 
+/**
+ * Opt-in flag for listing dot-prefixed entries in the path picker. Absent means
+ * off, so an old client keeps the previous behavior. It is a string rather than
+ * a boolean because it arrives as a query parameter; `'false'` is accepted (and
+ * means off) so a client can send the flag unconditionally.
+ */
+const showHiddenQuerySchema = z.enum(['true', 'false']).optional();
+
 /** Query validation for the lazy, allowlisted filesystem path picker. */
 export const FilesystemBrowseQuerySchema = z.object({
   path: filesystemPickerPathSchema.optional(),
@@ -73,6 +81,7 @@ export const FilesystemBrowseQuerySchema = z.object({
     .max(100)
     .regex(/^[a-zA-Z0-9_-]+$/, 'Invalid session id')
     .optional(),
+  showHidden: showHiddenQuerySchema,
 });
 
 /** Query validation for a single allowlisted path-picker file preview. */
@@ -83,6 +92,7 @@ export const FilesystemPreviewQuerySchema = z.object({
     .max(100)
     .regex(/^[a-zA-Z0-9_-]+$/, 'Invalid session id')
     .optional(),
+  showHidden: showHiddenQuerySchema,
 });
 
 /**

src/web/sensitive-path.ts

@@ -13,23 +13,73 @@
  * credentials, dotenv files) while leaving ordinary cross-workspace files
  * attachable.
  *
+ * ⚠️ The path picker's `showHidden` option is what makes the dot-prefixed half
+ * of this list load-bearing. Before it existed, the picker refused every path
+ * with a hidden segment, so `~/.config/gh/hosts.yml` and friends were
+ * unreachable by construction and the list only had to cover the few secrets
+ * that live in plain sight. Opting into hidden entries removes that accident,
+ * so every credential location below has to be named. Adding a new browse
+ * surface means re-reading this file, not assuming it already covers you.
+ *
+ * ⚠️ Deliberately NOT whole-tree blocks: `~/.codeman/` (the publish skill
+ * attaches from it) and `~/.claude/` (transcripts and team state are ordinary
+ * files worth attaching). Only their secret-bearing members are named.
+ *
  * Callers MUST resolve symlinks (realpath) BEFORE calling isSensitivePath so a
  * symlink pointing at a sensitive target is also caught.
  */
 
-import { homedir } from 'node:os';
-
 const SENSITIVE_PATTERNS: RegExp[] = [
+  // System account databases.
   /^\/etc\/shadow$/,
   /^\/etc\/gshadow$/,
   /^\/etc\/master\.passwd$/,
-  new RegExp(`^${homedir().replace(/[.*+?^${}()|[\]\\]/g, '\\$&')}\\/\\.ssh\\/`),
+
+  // SSH and GPG private key material. `.ssh/` is matched at any depth rather
+  // than only under homedir(): a per-project or per-deploy key directory holds
+  // exactly the same secret, and it drops a homedir() read that is captured at
+  // module load and therefore wrong for anything that changes HOME later.
+  /\/\.ssh\//,
+  /\/\.gnupg\//,
+
+  // Dotenv, in every conventional spelling (.env, .env.local, .env.production).
   /\/\.env$/,
   /\/\.env\./,
-  /\/credentials(\.json|\.yml|\.yaml|\.xml)?$/i,
-  /\/\.aws\/credentials$/,
+
+  // Generic credential files, plus the per-vendor spellings that do not match it.
+  /\/credentials(\.json|\.yml|\.yaml|\.xml|\.toml|\.db)?$/i,
+  /\/\.aws\/(credentials|config)$/,
+  /\/\.aws\/sso\/cache\//,
   /\/\.gcloud\/credentials\.db$/,
+  /\/\.config\/gcloud\//,
+  /\/\.azure\//,
   /\/\.docker\/config\.json$/,
+  /\/\.kube\/config$/,
+
+  // Package-registry and forge tokens. Each of these is a bearer credential in
+  // a plain-text dotfile, which is exactly what a path picker will surface.
+  /\/\.npmrc$/,
+  /\/\.yarnrc\.yml$/,
+  /\/\.git-credentials$/,
+  /\/\.config\/gh\//,
+  /\/\.config\/hub$/,
+  /\/\.netrc$/,
+  /\/_netrc$/,
+  /\/\.pypirc$/,
+  /\/\.gem\/credentials$/,
+  /\/\.cargo\/credentials(\.toml)?$/,
+  /\/\.terraformrc$/,
+  /\/\.terraform\.d\//,
+
+  // Database client credentials.
+  /\/\.pgpass$/,
+  /\/\.my\.cnf$/,
+
+  // Agent CLI credentials, including Codeman's own hook secret and user table.
+  // Named individually so the surrounding trees stay attachable (see above).
+  /\/\.claude\/\.credentials\.json$/,
+  /\/\.codeman[^/]*\/hook-secret$/,
+  /\/\.codeman[^/]*\/users\.json$/,
 ];
 
 /**