Review follow-up to 907e8d03e (ce-code-review, 8 personas):
- Ctrl/Cmd+V with no clipboard API (or after a denied read) now returns
false WITHOUT preventDefault: xterm skips key handling and the browser's
default paste fires xterm's helper-textarea listener once. Returning true
made non-mac xterm inject \x16 and cancel the native paste (verified
against xterm 5.5.0 _keyDown).
- A denied clipboard read sets a sticky ref so later pastes use the native
path instead of being preventDefaulted into zero delivery.
- Custom-path delivery goes through terminal.paste() to restore bracketed
paste and newline normalization.
- 'Start terminal' surfaces createTab failures in the error banner and
disables while a create is in flight (no duplicate PTY sessions).
- normalizeActiveTab() extracted so storage-read and server-validation
share one all-inactive tie-break; failure-path regression test added.
- Rewrote docs/solutions/ui-bugs/xterm-async-font-remeasure-paste-dedupe.md
to the current paste contract (was prescribing the pre-#1902 behavior).
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>