docs(plan): record planning artifacts for recent work streams

Add task_plan/findings/progress notes for knowledge fact fidelity,
brand description context, media supply favorites, and the workspace
sync-to-39 deployment.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

findings.media-supply-favorites.md

@@ -0,0 +1,12 @@
+# Media Supply Favorites Findings
+
+- Existing migration incorrectly enforces one group per resource with a unique
+  `(tenant_id, user_id, resource_id)` constraint.
+- Existing PostgreSQL upsert moves a resource between groups.
+- Existing favorites view fetches details for every favorite ID in batches of 100;
+  this must become a server-side search and pagination query.
+- Existing resources-page global removal remains a valid separate operation.
+- The new page query should join the selected group membership to visible model-1
+  resources, search by media name or supplier resource ID, and return a fixed 10 rows.
+- Group metadata may still return membership IDs for counts and the resources-page
+  global favorite indicator; resource details must no longer be loaded from that full set.