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.

frontend/src/adapters/rest.ts

@@ -13,7 +13,6 @@ import type { TitleEntry } from "../stores/titles";
 import type { User } from "../stores/session";
 import type { PublicConfig } from "../stores/config";
 import type {
-  Backlink,
   DeviceToken,
   ImportResult,
   NoteChanges,
@@ -80,7 +79,6 @@ export const rest: Repo = {
     list: async (query) => (await api.get<{ notes: Note[] }>(`/api/notes?${notesQuery(query)}`)).notes,
     get: (id) => api.get<Note>(`/api/notes/${id}`),
     create: (input: NoteCreateInput) => api.post<Note>("/api/notes", input),
-    createTitled: (title) => api.post<Note>("/api/notes", { title, body: "" }),
     update: (id, changes: NoteChanges) => api.patch<Note>(`/api/notes/${id}`, changes),
     completeReminder: (id) => api.post<Note>(`/api/notes/${id}/reminder/complete`),
     snoozeReminder: (id, minutes) => api.post<Note>(`/api/notes/${id}/reminder/snooze`, { minutes }),
@@ -103,9 +101,6 @@ export const rest: Repo = {
     reminders: async () => (await api.get<{ notes: Note[] }>("/api/notes/reminders")).notes,
     titles: async () => (await api.get<{ titles: TitleEntry[] }>("/api/notes/titles")).titles,
     search: async (q) => (await api.get<{ notes: Note[] }>(`/api/notes/search?q=${encodeURIComponent(q)}`)).notes,
-    backlinks: async (id) => (await api.get<{ backlinks: Backlink[] }>(`/api/notes/${id}/backlinks`)).backlinks,
-    linkSearch: async (q) =>
-      (await api.get<{ results: TitleEntry[] }>(`/api/notes/link-search?q=${encodeURIComponent(q)}`)).results,
   },
 
   savedFilters: {