docs: update CLAUDE.md with session learnings

- Bump migration count to 49
- Add chat conclusion and survey management to recently completed
- Add lessons #41-43: assistant chat state pattern, public page fetch pattern, EmailService pattern

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

CLAUDE.md

@@ -47,23 +47,25 @@ When adding new pages/components: use "ResolutionFlow" branding, ice-cyan gradie
 ## Current State
 
 - **Phase:** Phase 2.5 - Step Library Foundation (In Progress)
-- **Backend:** Complete (25+ API endpoints, 100+ integration tests)
+- **Backend:** Complete (35+ API endpoints, 100+ integration tests)
 - **Frontend:** Core features complete, Tree Editor functional
-- **Database:** PostgreSQL with Docker, 30+ migrations
+- **Database:** PostgreSQL with Docker, 49 migrations
 - **Detailed status:** [CURRENT-STATE.md](CURRENT-STATE.md)
 
 ### What's In Progress
 
-- Procedural flows reusability and run lifecycle improvements (Phase 2)
 - Step Library Frontend UI
 
 ### Recently Completed
 
-- Maintenance flows: `maintenance` tree_type, batch session launch, saved target lists, APScheduler cron scheduling, maintenance detail page
-- Session sharing: ShareSessionModal, SharedSessionPage, MySharesPage, share links with copy/manage
-- Procedural editor UX: section headers as step type, "More Options" collapsible, URL intake field, tag input improvements
-- Type-aware routing: centralized `getTreeNavigatePath` helper, procedural resume support, safety redirects
-- Export improvements (Phases A-C): step cutoff, summary block, detail levels, editable preview, sensitive data redaction
+- AI chat session conclusion: outcome tracking, AI-generated ticket summaries, resume flow
+- Survey completion: email-to-self, thank-you page, admin read/unread/archive/delete management
+- Survey system: public survey page, admin invite tracking, response viewer with CSV export
+- Email verification: tokens, banner, admin toggle (platform setting)
+- AI assistant: in-session copilot panel, standalone chat with RAG
+- Slate & Ice aesthetic redesign: glassmorphism, brand fonts, orchestrated animations
+- Account management: profile settings, delete/leave/transfer, chat retention
+- Maintenance flows: batch session launch, saved target lists, APScheduler scheduling
 
 ---
 
@@ -94,7 +96,7 @@ patherly/
 ├── backend/
 │   ├── app/
 │   │   ├── main.py                 # FastAPI entry point
-│   │   ├── api/endpoints/          # Route handlers (auth, trees, sessions, admin, steps, etc.)
+│   │   ├── api/endpoints/          # Route handlers (auth, trees, sessions, admin, steps, survey, copilot, assistant_chat)
 │   │   ├── api/deps.py             # Auth dependencies
 │   │   ├── api/router.py           # Route registration
 │   │   ├── core/                   # config, database, permissions, security, audit, rate_limit
@@ -112,6 +114,7 @@ patherly/
 │   │   ├── store/                  # Zustand stores (auth, treeEditor, proceduralEditor, userPreferences)
 │   │   └── types/                  # TypeScript interfaces
 │   └── tailwind.config.js
+├── docs/plans/archive/             # Archived design/impl docs (pre-March 2026)
 ├── CLAUDE.md                       # This file
 ├── CURRENT-STATE.md                # Detailed feature status
 ├── LESSONS-LEARNED.md              # (Deprecated — consolidated into CLAUDE.md)
@@ -304,8 +307,18 @@ navigate(`/trees/${newTree.id}/edit`)
 
 **37. First deployed user needs manual admin promotion:** New users default to `engineer` role. Promote via SQL: `UPDATE users SET role = 'admin' WHERE email = '...';` then re-login for new JWT.
 
+**39. Platform settings for feature toggles:** Use `SettingsManager.get("key", db, default=True)` to gate features. Add toggle in `admin/SettingsPage.tsx` (same pattern as `maintenance_mode`). Frontend can check status via a lightweight GET endpoint without auth.
+
+**40. Survey public routes:** `SurveyPage` is a public route (no auth). Survey invite tokens are passed as `?token=` query param. Add public pages at top level in `router.tsx` alongside `/login`.
+
 **38. Alembic migrations MUST use sequential numbered prefixes:** Check `backend/alembic/versions/` for the highest numbered migration and use the next number. Format: `XXX_descriptive_name.py` (e.g., `040_add_whatever.py`). NEVER use auto-generated revision IDs like `0f1ca2af3647`. Always pass `--rev-id` flag: `alembic revision --autogenerate -m "desc" --rev-id=040`.
 
+**41. Assistant chat uses local React state, not a Zustand store:** `AssistantChatPage.tsx` manages `chats`, `activeChatId`, `messages`, `input`, `loading` as `useState`. The `aiChatStore.ts` is for the AI Chat Builder (tree generation), NOT the standalone assistant. Don't look for a store when modifying assistant chat.
+
+**42. Public pages use raw `fetch()`, not `apiClient`:** Survey, shared sessions, and other no-auth pages call the API directly via `fetch()` with `${import.meta.env.VITE_API_URL || 'http://localhost:8000'}/api/v1/...`. Don't use `apiClient` — it requires auth tokens and uses relative paths.
+
+**43. Adding new email types:** Add static async method to `EmailService` in `core/email.py`. Pattern: check `settings.email_enabled`, import `resend`, build HTML string, call `resend.Emails.send()`, return `bool`. Always fire-and-forget from endpoints (log errors, don't fail the request).
+
 ---
 
 ## RBAC & Permissions