fix(soft-delete): filter trashed rows across read/write paths

Drift-audit Group 3 (soft-delete lifecycle gaps). Trashed rows were
leaking into reads and being mutated/resurrected by writes:

- update SELECTs now exclude trashed rows: update_milestone,
  update_project, update_event, and get_milestone_in_project (the latter
  backs all four milestone routes). Mutating a trashed row silently
  persisted and reappeared on restore.
- MCP get_recent (notes/projects/events) and list_tags now filter
  deleted_at IS NULL, so trashed items stop surfacing in the agent's
  bootstrap context and tag counts.
- convert_task_to_note clears recurrence_rule + recurrence_next_spawn_at
  so a demoted note can't spawn children via the (now-live) sweep.
- caldav pull skips locally-trashed events (by caldav_uid) instead of
  resurrecting them via update or creating a duplicate live copy.
- trash _cascade now stamps the FULL sub-task subtree (iterative descent),
  not just direct children, so deeply nested sub-tasks restore as one
  batch. Test updated for the new descent query.

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

src/fabledassistant/mcp/tools/recent.py

@@ -38,7 +38,8 @@ async def get_recent(days: int = 7, limit: int = 25) -> dict:
     items: list[dict] = []
     async with async_session() as session:
         notes = (await session.execute(
-            select(Note).where(Note.user_id == uid, Note.updated_at >= since)
+            select(Note).where(Note.user_id == uid, Note.updated_at >= since,
+                               Note.deleted_at.is_(None))
             .order_by(Note.updated_at.desc()).limit(limit)
         )).scalars().all()
         for n in notes:
@@ -50,7 +51,8 @@ async def get_recent(days: int = 7, limit: int = 25) -> dict:
             })
         projects = (await session.execute(
             select(Project).where(Project.user_id == uid,
-                                  Project.updated_at >= since)
+                                  Project.updated_at >= since,
+                                  Project.deleted_at.is_(None))
             .order_by(Project.updated_at.desc()).limit(limit)
         )).scalars().all()
         for p in projects:
@@ -62,7 +64,8 @@ async def get_recent(days: int = 7, limit: int = 25) -> dict:
             })
         events = (await session.execute(
             select(Event).where(Event.user_id == uid,
-                                Event.updated_at >= since)
+                                Event.updated_at >= since,
+                                Event.deleted_at.is_(None))
             .order_by(Event.updated_at.desc()).limit(limit)
         )).scalars().all()
         for e in events:

src/fabledassistant/mcp/tools/tags.py

@@ -39,7 +39,7 @@ async def list_tags(limit: int = 50) -> dict:
     limit = max(1, min(limit, 200))
     async with async_session() as session:
         result = await session.execute(
-            select(Note.tags).where(Note.user_id == uid)
+            select(Note.tags).where(Note.user_id == uid, Note.deleted_at.is_(None))
         )
         tag_lists = [row[0] for row in result.all()]
     counts = _aggregate_tag_counts(tag_lists)