Feat v0.5.3 chat polish (#33)

Co-authored-by: Jeffrey Smith <jasafpro@gmail.com>
Co-committed-by: Jeffrey Smith <jasafpro@gmail.com>

CHANGELOG.md

@@ -2,6 +2,42 @@
 
 All notable changes to Switchboard Core are documented here.
 
+## v0.5.3 — Chat Polish + Integration Testing
+
+### Added
+
+- **`db.query()` search_like**: New kernel-level `search_like` kwarg for text
+  search. Accepts `{col: pattern}` dict, generates OR-joined `LIKE` (SQLite) /
+  `ILIKE` (Postgres) clauses. Composes with existing `filters` via AND. Reusable
+  by any package. 5 new sandbox tests.
+- **Conversation search**: `GET /search?q=term` endpoint in `chat-core`. Searches
+  conversation titles and message content, scoped to user's conversations.
+  Returns `{conversations: [...], messages: [...]}`.
+- **Search UI**: Debounced search input in chat sidebar. Results view replaces
+  conversation list showing matched conversations and message snippets with
+  section headers. Click result to navigate, clear button to dismiss.
+- **`workflow-chat` library package**: `on_advance` hook that creates scoped
+  group conversations when workflow stages require team collaboration. Adds all
+  team members as participants, sends system message linking to the instance,
+  enriches `stage_data` with `conversation_id`. Idempotent — skips if
+  conversation already exists.
+- **Multi-user E2E test infrastructure**: `docker-compose-e2e.yml` with 2
+  replicas, Postgres, and nginx load balancer. `ci/e2e-chat-test.sh` shell
+  script covering auth, conversation CRUD, message send/read, cross-replica
+  consistency, search, and pagination. `ci/e2e-ws-listener.js` Node.js
+  WebSocket client for realtime event testing.
+- **Workflow hook tests**: 6 new Go tests for `parseOnAdvanceResult` covering
+  None, nil, error, enriched stage_data, non-dict, and nested structure cases.
+
+### Changed
+
+- **Message pagination polish**: Scroll position now preserved when loading older
+  messages — records `scrollHeight` before prepend, restores via
+  `requestAnimationFrame`. Loading spinner shown at top of thread during fetch.
+  "Load older messages" button hidden while loading.
+- **chat-core** bumped to v0.2.0 (new search endpoint).
+- **chat** bumped to v0.2.0 (search UI, pagination polish).
+
 ## v0.5.2 — Chat Surface
 
 ### Added