fix: fuzzy project resolution and guard against accidental project creation

- _resolve_project now uses reverse-substring + SequenceMatcher (≥0.55)
  so partial names like "Famous Supply" match "Famous Supply Co." reliably
- create_project runs similar-project checks before the confirmed gate so
  confirmed=true can't bypass them; threshold lowered to 0.55 to catch
  abbreviated names
- Error messages on project-not-found no longer suggest create_project,
  directing the model to list_projects first
- Tool description updated to explicitly prohibit calling create_project
  in response to a lookup failure
- tasks.py: fire-and-forget embedding update on create/update
- briefing_pipeline.py: await is_caldav_configured (was sync call)
- notes.py: remove erroneous duplicate count_query filter

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

src/fabledassistant/services/notes.py

@@ -157,7 +157,6 @@ async def list_notes(
         if no_project:
             query = query.where(Note.project_id.is_(None))
             count_query = count_query.where(Note.project_id.is_(None))
-            count_query = count_query.where(Note.parent_id == parent_id)
 
         sort_col = getattr(Note, sort, Note.updated_at)
         if order == "asc":