Remove [[wiki-links]], backlinks and the graph

Operator, 2026-08-22 (note 2897): ThoughtSync is an intermediary surface. You
write here because it's easy — a notebook in your pocket — and later you recall
the thing and go finish it somewhere else. Recall is the product; organization
is secondary. A linking system is organization, and it isn't what this is for.

So: `[[wiki-links]]`, backlinks, the `[[` autocomplete, the note_links table,
`/api/notes/link-search`, `/api/notes/<id>/backlinks`, the whole graph blueprint
and GraphView. Rust core loses `extract_links`, `backlinks`, `link_search` and
`create_titled`; the desktop loses the three Tauri commands that exposed them.

This subsumes 982d24c rather than reverting it. That commit bound links to a
note id so a rename would stop rewriting other notes' bodies — real infra, but
infra for a feature that is now gone, and nothing it added survives. Alembic
0023 stays in the chain anyway: it shipped in an image and may already be
applied, and deleting an applied revision strands a database's version pointer.
0024 drops the table and takes the column with it. The history stays honest
about the fact that it existed for a day.

Two things deliberately kept, because they were serving recall and only
incidentally serving links:

- `/api/notes/titles` and the titles store. The command palette lists them so
  you can jump to a note by name. `resolve()` — the name→note lookup that only
  linking needed — is gone.
- `display_title`. Every note still has a name for search results and export
  filenames. What that name is FOR changed; that it exists did not.

`notes/links.py` is now `notes/tags.py`, holding the #tag→label reconciliation
it always also owned. A file called links.py with no links in it would have been
exactly the drift this removal is meant to end.

Also swept out on the way: `_escape_like`, whose only caller was link-search,
and the `graph` icon. Nothing lost that a person typed — note_links was always
derived, and the `[[text]]` is still sitting in every body it was written in.

src/thoughtsync/sync.py

@@ -28,8 +28,6 @@ from .models.note_item import NoteItem
 from .models.note_revision import NoteRevision
 from .notes import (
     _reconcile_tags,
-    _claim_unresolved_links,
-    _rewrite_links,
     _serialize_notes,
     derive_display_title,
     normalize_color,
@@ -282,7 +280,7 @@ async def _apply_note(db, ch: dict) -> dict:
     elif note.purged_at is not None:
         note.purged_at = None  # client re-created/edited → clear the tombstone
 
-    old_title, old_body, old_display = note.title, note.body, note.display_title
+    old_title, old_body = note.title, note.body
     _assign_note_fields(note, ch)
     note.display_title = derive_display_title(note.title, note.body)
     if edited_at is not None:
@@ -292,15 +290,8 @@ async def _apply_note(db, ch: dict) -> dict:
         db.add(NoteRevision(note_id=note.id, title=old_title, body=old_body))
     await db.flush()  # assign note.id before items/labels/links
     await _apply_note_items(db, note, ch)
-    await _rewrite_links(db, note)
     await _reconcile_tags(db, note)
     await _apply_note_manual_labels(db, note, ch)
-    # Any change to the name — including a note arriving for the first time, where
-    # the old name was empty — may be what unresolved inbound links were waiting for.
-    # Nothing else's body is touched; see _claim_unresolved_links.
-    new_display = note.display_title
-    if old_display != new_display:
-        await _claim_unresolved_links(db, note)
     await db.flush()
     await db.refresh(note, ["sync_revision"])
     return {