docs: update TASKS.md and scratchpad for CLI command architecture (#159)

Co-authored-by: Jason Woltje <jason@diversecanvas.com>
Co-committed-by: Jason Woltje <jason@diversecanvas.com>

docs/scratchpads/mvp-20260312.md

@@ -222,3 +222,19 @@ Issues closed: #52, #55, #57, #58, #120-#134
 - Infrastructure: coord DB migration, agent sandbox hardening
 - Quality: E2E Playwright suite (~35 tests), comprehensive docs (user/admin/dev/deployment)
 - Fixes: TUI state updater, agent session sandboxing
+
+### Session 13 — CLI Command Architecture (P8-005, P8-006)
+
+| Session | Date       | Milestone | Tasks Done     | Outcome                                                                                                       |
+| ------- | ---------- | --------- | -------------- | ------------------------------------------------------------------------------------------------------------- |
+| 13      | 2026-03-15 | Phase 8   | P8-005, P8-006 | CLI command architecture implemented. DB schema, brain repo, gateway endpoints, CLI commands. PR #158 merged. |
+
+**Changes delivered:**
+
+- DB: Extended agents table (projectId, ownerId, systemPrompt, allowedTools, skills, isSystem). Added agentId to conversations.
+- Brain: New agents repository with findAccessible (owner's + system agents).
+- Gateway: /api/agents CRUD, consolidated /api/missions with user-scoped CRUD + /tasks sub-routes, coord slimmed to file-based only, agentConfigId wired into session creation.
+- CLI: `mosaic agent` (--list, --new, --show, --update, --delete), `mosaic mission` (--list, --init, --plan, --update, task subcommand), `mosaic prdy` (gateway-aware), shared with-auth + select-dialog utilities.
+- TUI: --agent and --project flags, agent name display in top bar, agentId in socket payload.
+- Types: agentId added to ChatMessagePayload.
+- Tests: 23/23 gateway tests pass (updated ownership test for user-scoped missions).