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.

core/src/local/store.rs

@@ -350,61 +350,6 @@ pub fn search(conn: &Connection, q: &str) -> rusqlite::Result<Vec<Note>> {
     ids.iter().map(|id| load_note(conn, id)).collect()
 }
 
-pub fn backlinks(conn: &Connection, id: &str) -> rusqlite::Result<Vec<Backlink>> {
-    let target: String = {
-        let (t, b): (Option<String>, String) =
-            conn.query_row("SELECT title, body FROM notes WHERE id = ?1", [id], |r| {
-                Ok((r.get(0)?, r.get(1)?))
-            })?;
-        display_title(t.as_deref(), &b)
-    };
-    if target.is_empty() {
-        return Ok(Vec::new());
-    }
-    let mut stmt =
-        conn.prepare("SELECT id, title, body FROM notes WHERE trashed = 0 AND id != ?1")?;
-    let rows = stmt.query_map([id], |r| {
-        let nid: String = r.get(0)?;
-        let t: Option<String> = r.get(1)?;
-        let b: String = r.get(2)?;
-        Ok((nid, t, b))
-    })?;
-    let mut out = Vec::new();
-    for row in rows {
-        let (nid, t, b) = row?;
-        if derive::extract_links(&b)
-            .iter()
-            .any(|l| l.eq_ignore_ascii_case(&target))
-        {
-            out.push(Backlink {
-                id: nid,
-                title: display_title(t.as_deref(), &b),
-            });
-        }
-    }
-    Ok(out)
-}
-
-pub fn link_search(conn: &Connection, q: &str) -> rusqlite::Result<Vec<TitleEntry>> {
-    let ql = q.trim().to_lowercase();
-    let mut stmt = conn.prepare("SELECT id, title, body FROM notes WHERE trashed = 0")?;
-    let rows = stmt.query_map([], |r| {
-        let id: String = r.get(0)?;
-        let t: Option<String> = r.get(1)?;
-        let b: String = r.get(2)?;
-        Ok((id, t, b))
-    })?;
-    let mut out = Vec::new();
-    for row in rows {
-        let (id, t, b) = row?;
-        let dt = display_title(t.as_deref(), &b);
-        if ql.is_empty() || dt.to_lowercase().contains(&ql) {
-            out.push(TitleEntry { id, title: dt });
-        }
-    }
-    Ok(out)
-}
-
 // ---- notes: write -----------------------------------------------------------
 
 pub fn create_note(conn: &Connection, input: &NoteCreateInput) -> rusqlite::Result<Note> {
@@ -434,30 +379,6 @@ pub fn create_note(conn: &Connection, input: &NoteCreateInput) -> rusqlite::Resu
     load_note(conn, &id)
 }
 
-pub fn create_titled(conn: &Connection, title: &str) -> rusqlite::Result<Note> {
-    let input = NoteCreateInput {
-        title: title.to_string(),
-        body: String::new(),
-        color: "default".to_string(),
-        kind: None,
-        items: None,
-    };
-    create_note(conn, &input)
-}
-
-fn snapshot_revision(conn: &Connection, id: &str) -> rusqlite::Result<()> {
-    let (title, body): (Option<String>, String) =
-        conn.query_row("SELECT title, body FROM notes WHERE id = ?1", [id], |r| {
-            Ok((r.get(0)?, r.get(1)?))
-        })?;
-    conn.execute(
-        "INSERT INTO note_revisions (id, note_id, title, body, created_at) VALUES (?1, ?2, ?3, ?4, ?5)",
-        params![new_id(), id, title, body, now()],
-    )?;
-    Ok(())
-}
-
-/// PATCH semantics: apply exactly the fields present in `changes`.
 pub fn update_note(conn: &Connection, id: &str, changes: &Value) -> rusqlite::Result<Note> {
     let obj = changes
         .as_object()