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>

docs/predictive-echo-plan.md

@@ -83,6 +83,14 @@ rules and why each exists:
 - **No drop on baseY change**: codex streams push lines to history while the
   composer stays viewport-pinned; predictions are row-relative to the pinned
   composer and remain valid (measured above).
+- **Anchor hold** (added by the independent post-build review): after any wire
+  input whose cursor effect the display has not shown yet (backspace with
+  nothing outstanding = deleting echoed text, every 'clear'-classified input,
+  an IME/plain-paste 'text' commit, and the bypass send paths), new
+  predictions are suppressed until the next PARSED write. Anchoring on the
+  stale cursor painted ghosts one cell off ("tehh" on backspace-then-retype
+  within RTT), blank-neutral and therefore TTL-lived. Worst case is exactly
+  one unpredicted keystroke: its own echo is a write, which releases the hold.
 - **predictBackspace()** pops the newest outstanding record (informational
   return; the consumer forwards `\x7f` unconditionally). Deleting already-echoed
   text renders at RTT in v1.