feat: Read My Mind phase 1, per-case intent profiles (capture + API + skill)

Per-case profiles of user intent (docs/readmymind-plan.md): user-stated goals
plus the user's recently submitted prompts, captured from the Claude session
transcript behind the new synced readMyMindEnabled setting (default OFF).

- intent-store.ts: keyed by owner + realpath(workingDir), FIFO/size caps,
  consecutive-dupe collapse, atomic 0600 writes to ~/.codeman/intents.json
- transcript-watcher.ts: new transcript:user_prompt event for typed user turns
  (tool_result-only entries stay silent); capture wiring in server.ts is
  claude-only and gated on the setting per event
- readmymind-routes.ts: GET/PUT/DELETE /api/sessions/:id/intent, ownership
  via findSessionOrFail, strict Zod schema
- agent skill: SKILL.md recipe + endpoints.md rows so agents can read and
  record intent (PUT replaces: read + merge; never delete unprompted)
- groundwork for the phase-2 predictor button; nothing is ever auto-sent

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/intent-store.ts

@@ -0,0 +1,233 @@
+/**
+ * @fileoverview Read My Mind intent store: per-case profiles of user intent.
+ *
+ * Feeds the Read My Mind predictor (`docs/readmymind-plan.md`). Each profile
+ * pairs user/agent-stated `goals` with the user's recently captured prompts,
+ * keyed by owner + realpath(workingDir) so the profile survives `/clear`,
+ * respawns, and session churn, and so multi-user scoping is structural (two
+ * owners of the same directory get distinct profiles).
+ *
+ * Capture rides the session transcript (`transcript:user_prompt`), not the
+ * input paths: `POST /input` sees only programmatic prompts and the WS channel
+ * delivers raw keystrokes, so neither yields clean submitted prompts.
+ *
+ * Prompts can contain secrets, so the state file is written 0600 (same posture
+ * as `users.json`) and the store is never fed into `/api/search`.
+ *
+ * Pure helpers (`deriveIntentKey`, `sanitizePromptText`, `isCapturablePrompt`,
+ * `appendPrompt`) are exported for unit tests; the `IntentStore` class adds the
+ * IO. Writes are atomic (tmp + rename) and synchronous: mutations arrive at
+ * human prompting pace, so there is nothing to debounce and no timer to leak.
+ */
+
+import { createHash } from 'node:crypto';
+import { existsSync, mkdirSync, readFileSync, realpathSync, renameSync, writeFileSync } from 'node:fs';
+import { dirname } from 'node:path';
+import { dataPath } from './config/instance.js';
+import type { IntentProfile, IntentPromptEntry } from './types/index.js';
+
+// ========== Limits ==========
+
+/** Max stored profiles; lowest `updatedAt` is evicted first. */
+export const MAX_INTENT_PROFILES = 200;
+
+/** Max captured prompts per profile (FIFO). */
+export const MAX_RECENT_PROMPTS = 50;
+
+/** Max characters kept per captured prompt. */
+export const MAX_PROMPT_CHARS = 500;
+
+/** Max characters for the `goals` field. */
+export const MAX_GOALS_CHARS = 8192;
+
+/** Prompts shorter than this are menu digits / Esc artifacts, not intent. */
+const MIN_PROMPT_CHARS = 3;
+
+// ========== Pure helpers ==========
+
+/** Stable per-case key: owner + resolved workingDir, hashed. */
+export function deriveIntentKey(owner: string | undefined, workingDir: string): string {
+  return createHash('sha256')
+    .update(`${owner ?? ''}:${workingDir}`)
+    .digest('hex')
+    .slice(0, 16);
+}
+
+/**
+ * Transcript user entries that are not typed intent: local slash-command echo,
+ * hook/system wrappers, and interrupt markers.
+ */
+export function isCapturablePrompt(text: string): boolean {
+  if (text.includes('<command-name>') || text.includes('<local-command-stdout>')) return false;
+  if (text.startsWith('<system-reminder>')) return false;
+  if (text.startsWith('Caveat: The messages below')) return false;
+  if (text.startsWith('[Request interrupted')) return false;
+  return true;
+}
+
+/**
+ * Collapse a transcript prompt to a bounded single line, or null when it is
+ * too short to mean anything (menu digits, Esc artifacts).
+ */
+export function sanitizePromptText(raw: string): string | null {
+  const text = raw
+    .replace(/[\r\n]+/g, ' ')
+    // eslint-disable-next-line no-control-regex
+    .replace(/[\x00-\x08\x0b-\x1f\x7f]/g, '')
+    .trim();
+  if (text.length < MIN_PROMPT_CHARS) return null;
+  return text.length > MAX_PROMPT_CHARS ? text.slice(0, MAX_PROMPT_CHARS) : text;
+}
+
+/**
+ * Fold one prompt into a profile: consecutive duplicates collapse (auto-resume
+ * "continue" spam), FIFO cap applies. Returns a new profile object.
+ */
+export function appendPrompt(profile: IntentProfile, entry: IntentPromptEntry): IntentProfile {
+  const last = profile.recentPrompts[profile.recentPrompts.length - 1];
+  if (last && last.text === entry.text) {
+    return { ...profile, updatedAt: entry.ts };
+  }
+  const recentPrompts = [...profile.recentPrompts, entry].slice(-MAX_RECENT_PROMPTS);
+  return { ...profile, recentPrompts, updatedAt: entry.ts };
+}
+
+// ========== Store ==========
+
+interface IntentStoreFile {
+  version: 1;
+  profiles: IntentProfile[];
+}
+
+export class IntentStore {
+  private profiles: Map<string, IntentProfile> | null = null;
+
+  private get filePath(): string {
+    return dataPath('intents.json');
+  }
+
+  // ----- Public API -----
+
+  /**
+   * The profile for a session's case. Never persists on read: an absent
+   * profile returns an empty transient one (`updatedAt: 0`).
+   */
+  getProfile(owner: string | undefined, workingDir: string): IntentProfile {
+    const dir = this.resolveDir(workingDir);
+    const key = deriveIntentKey(owner, dir);
+    return this.load().get(key) ?? this.emptyProfile(key, dir);
+  }
+
+  /**
+   * Capture one submitted prompt. Returns true when it was recorded (passed
+   * the capturability filter and sanitization).
+   */
+  recordPrompt(
+    owner: string | undefined,
+    workingDir: string,
+    sessionId: string,
+    rawText: string,
+    ts: number = Date.now()
+  ): boolean {
+    if (!isCapturablePrompt(rawText)) return false;
+    const text = sanitizePromptText(rawText);
+    if (text === null) return false;
+
+    const dir = this.resolveDir(workingDir);
+    const key = deriveIntentKey(owner, dir);
+    const profiles = this.load();
+    const profile = profiles.get(key) ?? this.emptyProfile(key, dir);
+    profiles.set(key, appendPrompt(profile, { ts, sessionId, text }));
+    this.evictOverflow(profiles);
+    this.persist();
+    return true;
+  }
+
+  /** Replace the goals text (bounded). Returns the updated profile. */
+  setGoals(owner: string | undefined, workingDir: string, goals: string): IntentProfile {
+    const dir = this.resolveDir(workingDir);
+    const key = deriveIntentKey(owner, dir);
+    const profiles = this.load();
+    const profile = profiles.get(key) ?? this.emptyProfile(key, dir);
+    const updated: IntentProfile = { ...profile, goals: goals.slice(0, MAX_GOALS_CHARS), updatedAt: Date.now() };
+    profiles.set(key, updated);
+    this.evictOverflow(profiles);
+    this.persist();
+    return updated;
+  }
+
+  /** Forget everything for a case. Returns true when a profile existed. */
+  deleteProfile(owner: string | undefined, workingDir: string): boolean {
+    const dir = this.resolveDir(workingDir);
+    const key = deriveIntentKey(owner, dir);
+    const profiles = this.load();
+    const existed = profiles.delete(key);
+    if (existed) this.persist();
+    return existed;
+  }
+
+  // ----- Internals -----
+
+  private emptyProfile(key: string, workingDir: string): IntentProfile {
+    return { key, workingDir, updatedAt: 0, goals: '', recentPrompts: [] };
+  }
+
+  private resolveDir(workingDir: string): string {
+    try {
+      return realpathSync(workingDir);
+    } catch {
+      return workingDir;
+    }
+  }
+
+  private load(): Map<string, IntentProfile> {
+    if (this.profiles) return this.profiles;
+    this.profiles = new Map();
+    try {
+      if (existsSync(this.filePath)) {
+        const parsed = JSON.parse(readFileSync(this.filePath, 'utf-8')) as IntentStoreFile;
+        if (parsed && Array.isArray(parsed.profiles)) {
+          for (const profile of parsed.profiles) {
+            if (profile && typeof profile.key === 'string') this.profiles.set(profile.key, profile);
+          }
+        }
+      }
+    } catch (err) {
+      console.warn(`[IntentStore] Failed to load ${this.filePath}, starting empty:`, err);
+    }
+    return this.profiles;
+  }
+
+  private evictOverflow(profiles: Map<string, IntentProfile>): void {
+    while (profiles.size > MAX_INTENT_PROFILES) {
+      let oldestKey: string | null = null;
+      let oldestAt = Infinity;
+      for (const [key, profile] of profiles) {
+        if (profile.updatedAt < oldestAt) {
+          oldestAt = profile.updatedAt;
+          oldestKey = key;
+        }
+      }
+      if (oldestKey === null) return;
+      profiles.delete(oldestKey);
+    }
+  }
+
+  private persist(): void {
+    if (!this.profiles) return;
+    const file: IntentStoreFile = { version: 1, profiles: [...this.profiles.values()] };
+    const tmpPath = `${this.filePath}.tmp`;
+    try {
+      // dataPath()'s own mkdir is once-per-process; per-file test HOMEs need this.
+      mkdirSync(dirname(this.filePath), { recursive: true });
+      // 0600: captured prompts can contain secrets (same posture as users.json).
+      writeFileSync(tmpPath, JSON.stringify(file, null, 2), { mode: 0o600 });
+      renameSync(tmpPath, this.filePath);
+    } catch (err) {
+      console.warn(`[IntentStore] Failed to persist ${this.filePath}:`, err);
+    }
+  }
+}
+
+/** Module-level singleton, same pattern as `approvalInbox` (web/approval-inbox.ts). */
+export const intentStore = new IntentStore();