feat(notes): list + update + append + add_tag tools for the AI

Makes the "read all notes and tag them #Natur/#Technologie/…" use case
fully functional. Four new ModuleTool entries in notes/tools.ts:

- list_notes(limit?, query?, includeArchived?) — auto, read-only. Returns
  id + title + excerpt so the planner can reference concrete notes
  without dumping full bodies.
- update_note(noteId, title?, content?) — proposable. Destructive full
  overwrite. Docstring nudges toward append_to_note when applicable.
- append_to_note(noteId, content) — proposable, non-destructive. Handles
  the trailing-newline separator so markdown stays clean.
- add_tag_to_note(noteId, tag) — proposable, idempotent, case-insensitive.
  Strips leading #, replaces spaces with _, skips if already present.
  Exactly the categorization primitive the user asked for.

All three writes are added to AI_PROPOSABLE_TOOL_NAMES so both the
webapp policy and mana-ai's boot-time drift guard agree (now 11 tools).
Mirrored in services/mana-ai/src/planner/tools.ts.

AiProposalInbox mounted on /notes so approvals land inline in the
notes module too (already appears in the mission-detail cross-module
inbox via the earlier commit).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

packages/shared-ai/src/policy/proposable-tools.ts

@@ -25,6 +25,9 @@ export const AI_PROPOSABLE_TOOL_NAMES = [
 	'visit_place',
 	'undo_drink',
 	'save_news_article',
+	'update_note',
+	'append_to_note',
+	'add_tag_to_note',
 ] as const;
 
 export type AiProposableToolName = (typeof AI_PROPOSABLE_TOOL_NAMES)[number];