fix(review): harden + wire remote-host SSH cases end-to-end (PR #145)

- UI: add the missing data-tab="case-remote" tab button; dispatch it through
  submitCaseModal()/switchCaseModalTab() to linkRemoteCase() (was dead code).
- Restore: restoreMuxSessions() now passes remote (muxSession.remote ??
  savedState.remote) into the Session constructor, so remote metadata round-trips
  on restart instead of reattaching from a local cwd / respawning LOCAL / being
  erased from state.json. Recovery tests added.
- Run flows: runClaude()/runShell() route remote cases through /api/quick-start
  (POST /api/sessions stat-validates workingDir locally); run*() skip the
  /api/*/status pre-check and omit inert config/env for remote cases.
- Quick-start: resolve the remote case BEFORE the local CLI availability gates and
  skip isCodex/Gemini/OpenCodeAvailable() when remote; REJECT
  envOverrides/effort/codex/gemini/openCode config for remote (they don't cross
  ssh) instead of silently dropping them.
- Injection: reject $, backtick, $( in remotePath + identityFile at the schema
  layer (they survive shellescape into the bash -c launch double-quote layer).
  Regression tests for $(...) and backtick payloads added.
- Remote socket/name: launch on a DEDICATED -L codeman-remote socket under a
  codeman-ssh-<id> name that fails a remote Codeman's SAFE_MUX_NAME_PATTERN, so a
  remote instance can't adopt the session; scope tmux set-options per-session
  (never -g) so they don't mutate other sessions.
- Kill: best-effort ssh 'tmux -L codeman-remote kill-session' on remote session
  kill (fire-and-forget, never blocks/throws the local kill) so the remote agent
  isn't orphaned forever.
- Probe: wire checkRemoteTmuxAvailable() into POST /api/quick-start (structured
  OPERATION_FAILED) and as courtesy validation in remote-link; add a default
  -o ConnectTimeout=10 to buildSshConnectionArgs (overridable via extraSshOptions).
- Command default: remote claude default is now
  'exec claude --dangerously-skip-permissions' (per-host override stays the escape
  hatch), mirroring local non-interactive semantics.

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

test/routes/session-routes.test.ts

@@ -29,13 +29,19 @@ vi.mock('node:child_process', async (orig) => {
 });
 
 // In-memory remote store so remote-case tests can inject hosts/cases without real JSON files.
-const remoteStore = vi.hoisted(() => ({ hosts: [] as unknown[], cases: [] as unknown[] }));
+const remoteStore = vi.hoisted(() => ({
+  hosts: [] as unknown[],
+  cases: [] as unknown[],
+  tmuxCheck: { ok: true, tmuxPath: '/usr/bin/tmux' } as { ok: boolean; tmuxPath?: string; error?: string },
+}));
 vi.mock('../../src/remote-hosts.js', async (orig) => {
   const actual = await orig<typeof import('../../src/remote-hosts.js')>();
   return {
     ...actual,
     readRemoteHosts: vi.fn(async () => remoteStore.hosts),
     readRemoteCases: vi.fn(async () => remoteStore.cases),
+    // Stub the remote-tmux prereq probe so quick-start never shells out to ssh.
+    checkRemoteTmuxAvailable: vi.fn(async () => remoteStore.tmuxCheck),
   };
 });
 
@@ -90,9 +96,10 @@ describe('session-routes', () => {
 
   beforeEach(async () => {
     harness = await createEnvelopeHarness(registerSessionRoutes);
-    // Reset remote store so tests start with empty hosts/cases
+    // Reset remote store so tests start with empty hosts/cases and a passing tmux probe
     remoteStore.hosts = [];
     remoteStore.cases = [];
+    remoteStore.tmuxCheck = { ok: true, tmuxPath: '/usr/bin/tmux' };
   });
 
   afterEach(async () => {
@@ -861,6 +868,61 @@ describe('session-routes', () => {
       }
     });
 
+    it('rejects a remote quick-start that carries envOverrides (inert over ssh)', async () => {
+      remoteStore.hosts = [{ id: 'gpu-box', label: 'GPU Box', host: '10.0.0.42', username: 'ubuntu' }];
+      remoteStore.cases = [{ name: 'gpu-work', type: 'remote', hostId: 'gpu-box', remotePath: '/home/ubuntu/work' }];
+
+      const res = await harness.app.inject({
+        method: 'POST',
+        url: '/api/quick-start',
+        payload: { caseName: 'gpu-work', mode: 'claude', envOverrides: { CLAUDE_CODE_FOO: 'bar' } },
+      });
+
+      expect(res.statusCode).toBe(httpStatusForErrorCode(ApiErrorCode.INVALID_INPUT));
+      expect(JSON.parse(res.body)).toMatchObject({ success: false, errorCode: ApiErrorCode.INVALID_INPUT });
+    });
+
+    it('rejects a remote quick-start when the remote host lacks tmux', async () => {
+      remoteStore.hosts = [{ id: 'gpu-box', label: 'GPU Box', host: '10.0.0.42', username: 'ubuntu' }];
+      remoteStore.cases = [{ name: 'gpu-work', type: 'remote', hostId: 'gpu-box', remotePath: '/home/ubuntu/work' }];
+      remoteStore.tmuxCheck = {
+        ok: false,
+        error: 'remote host 10.0.0.42 needs tmux installed for durable remote sessions',
+      };
+
+      const res = await harness.app.inject({
+        method: 'POST',
+        url: '/api/quick-start',
+        payload: { caseName: 'gpu-work', mode: 'shell' },
+      });
+
+      expect(res.statusCode).toBe(httpStatusForErrorCode(ApiErrorCode.OPERATION_FAILED));
+      expect(JSON.parse(res.body)).toMatchObject({ success: false, errorCode: ApiErrorCode.OPERATION_FAILED });
+    });
+
+    it('does not run local codex availability check for a remote codex case', async () => {
+      // A remote codex case must NOT be blocked by the LOCAL codex availability gate
+      // (the CLI runs on the remote host). Probe is stubbed ok in remoteStore.tmuxCheck.
+      const startInteractive = vi.spyOn(Session.prototype, 'startInteractive').mockResolvedValue(undefined);
+      try {
+        remoteStore.hosts = [
+          { id: 'gpu-box', label: 'GPU Box', host: '10.0.0.42', username: 'ubuntu', commands: { codex: 'exec codx' } },
+        ];
+        remoteStore.cases = [{ name: 'gpu-work', type: 'remote', hostId: 'gpu-box', remotePath: '/home/ubuntu/work' }];
+
+        const res = await harness.app.inject({
+          method: 'POST',
+          url: '/api/quick-start',
+          payload: { caseName: 'gpu-work', mode: 'codex' },
+        });
+
+        expect(res.statusCode).toBe(200);
+        expect(JSON.parse(res.body).success).toBe(true);
+      } finally {
+        startInteractive.mockRestore();
+      }
+    });
+
     it('creates session with valid resumeSessionId', async () => {
       const res = await harness.app.inject({
         method: 'POST',