Change agent interaction

Rules: PRIVACY_SECURITY.md (the hook fails open; auth fails closed), ARCHITECTURE.md (contracts are additive), TESTING.md.

1. Red — state machine in core/src/domain/message.test.ts; behavior in core/src/application/inbox-service.test.ts (claim exactly once, requireAwaiting, long-poll via ManualScheduler).
2. Transports — adapters/src/http/http-api.test.ts (401/403/404/429/success) and desktop/src/main/ipc-api.test.ts (validation, error mapping).
3. Hook — hooks/agent-office-hook.test.ts:
   • Stop → {"decision":"block","reason":…} only when messages exist; posts last_assistant_message with requireAwaiting: true first.
   • UserPromptSubmit → hookSpecificOutput.additionalContext.
   • Server down / bad JSON / missing token / timeout → no output, exit 0, within 1.5s.
   • Message text is only ever passed to Claude as text — never to a shell.
4. Install — core/src/domain/hook-config.test.ts + hook-service.test.ts (idempotent, outdated → heal, foreign hooks untouched), FsHookRunner contract (wrapper runs the app binary with ELECTRON_RUN_AS_NODE=1), scripts/hook-install.test.ts (dev CLI).
5. E2E — packages/adapters/test/e2e.chat.test.ts (generic agent) and e2e.claude-code.test.ts (tailer + real hook script); e2e.security.test.ts stays green; app specs desktop/e2e/{chat,settings}.spec.ts.
6. UI — web/src/app/view-models.ts (panelVM, hintFor, connectVM, emptyStateVM) tests, then adapters/dom/{panel,connect-panel,empty-state}.ts with textContent only. Strings live in web/src/app/connect-copy.ts. Connection status reaches the UI as ConnectionInfo (shared/src/desktop-api.ts, built in desktop/src/main/composition.ts); it must never carry the token. The hook wrapper sets AGENT_OFFICE_URL from the live port (FsHookRunner), and a port change heals it.
7. Manual check with a real session (ask the user first — it edits their real ~/.claude/settings.json): make dev, Settings → Install hook, message a working Claude Code session; the reply should appear when its turn ends. Uninstall afterwards if it was only for testing.

Known limit: Claude Code has no hook that can wake an idle session; messages to a waiting session arrive on the user's next prompt. Keep the UI hint honest about this.

Managed sessions (/interaction-change also covers them): the core service is core/src/application/managed-session-service.ts behind ManagedSessions and ComposeMessage; the SDK adapter is adapters/src/agents/claude-sdk-runner.ts (contract agentRunnerContract; the scripted runner AGENT_OFFICE_FAKE_RUNNER=1 drives desktop/e2e/session.spec.ts). Context paths stay in main behind ctx_ refs. The hook exits early when AGENT_OFFICE_MANAGED=1. Strings live in web/src/app/session-copy.ts.