fix(predictive-echo): anchor hold after unpredicted wire edits (review findings)

Independent post-build review found three gaps, all one family: input that
changes the composer without a prediction leaves the DISPLAYED cursor stale
for one RTT, and anchoring a new run on it painted ghosts one cell off
(blank-neutral, so they lived out the full TTL: "tehh" on
backspace-then-retype, exactly on the links the feature targets).

Fix: the addon now HOLDS new predictions after any such edit (backspace with
nothing outstanding = deleting echoed text, clearPredictions, and now also
IME/plain-paste 'text' commits, which the hook clears like 'clear') until
the next PARSED write releases the hold. The inline predictChar reconcile
deliberately does not count: only the emitter pass or the public
reconcile() is the display-caught-up contract. Worst case is exactly one
unpredicted keystroke, whose own echo releases the hold. Also patched the
one bypass path the PR had missed: _handleCjkInput now clears predictions
like insertTerminalText and the other bypass sends.

Package suite 230, vm gating 85, E2E 10/10 all green after the change.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

packages/xterm-zerolag-input/test/codex-replay.test.ts

@@ -62,7 +62,7 @@ async function replay(name: string) {
       let painted = false;
       if (kind === 'char') painted = addon.predictChar(line.data);
       else if (kind === 'backspace') addon.predictBackspace();
-      else if (kind === 'clear') addon.clearPredictions();
+      else addon.clearPredictions(); // 'clear' AND 'text', like the terminal-ui hook
       // Span/record parity and grid bounds hold at every step
       expect(rt.spanCount()).toBe(addon.state.outstanding);
       assertSpansInGrid(rt);