test(tiles): the connect() static guard's end anchor resolves again

terminal-tile-unit slices connect() out of terminal-tile.js up to
'async _loadBuffer()'. The load queue commit (fca7acd0) gave _loadBuffer a
`{ refresh }` parameter, so that anchor stopped matching, indexOf returned
-1 and the slice ran to the end of the file: every check in the test
passed against code outside connect(). The anchor is now
'async _loadBuffer(' and the test asserts both anchors resolve, so a rename
fails it instead of widening it (checked by putting the old anchor back).

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

test/terminal-tile-unit.test.ts

@@ -792,7 +792,13 @@ describe('TerminalTile scroll-to-top history pull', () => {
   it('connect() installs the wheel listener (static guard)', () => {
     // connect() needs a whole xterm to run, so its wiring is pinned by source
     // rather than executed; the listener's behaviour is exercised above.
-    const connect = SOURCE.slice(SOURCE.indexOf('async connect()'), SOURCE.indexOf('async _loadBuffer()'));
+    const start = SOURCE.indexOf('async connect()');
+    const end = SOURCE.indexOf('async _loadBuffer(');
+    // Both anchors must resolve, or the slice runs to the end of the file and
+    // every check below passes against code outside connect().
+    expect(start).toBeGreaterThan(-1);
+    expect(end).toBeGreaterThan(start);
+    const connect = SOURCE.slice(start, end);
     expect(connect).toContain('this._installWheelListener();');
     expect(connect).toContain('this._onLiveClear();');
     expect(connect).not.toContain('this.terminal.clear();');