Follow-up to the PR #112 re-review (all six prior blockers were already
resolved; these are new issues the rework introduced):
- app.js: define the missing `_scheduleTerminalRepaint()` helper. It was
called from both WebGL-fallback paths (onContextLoss + long-task trip)
but defined nowhere, so each fallback threw `TypeError` and lost the
post-fallback repaint, leaving a stale/blank terminal. Implemented as an
rAF-debounced full refresh (matches the old inline `terminal.refresh`).
- app.js: clear terminal load-state on the two post-write stale-select
early-returns (cached-buffer + rewrite branches), matching the other
four checks. Switching away from a mid-loading tab no longer leaks a
permanent `.tab-loading` spinner / `aria-busy=true`.
- terminal-ui.js + app.js: gate the post-resize TUI-redraw settle on an
actual dimension change. `sendResize` now returns whether dims changed;
a same-size tab switch sends no SIGWINCH, so the wait is skipped instead
of charging a flat tax on every non-shell switch. Literal hoisted to
`TUI_REDRAW_SETTLE_MS`.
- tmux-manager.ts: `resizeWindow()` uses a non-blocking `exec` instead of
`execSync` so the interactive WS/HTTP resize path can't stall the
Fastify event loop on a slow/hung tmux. Sole caller already fire-and-
forgets the result; test updated to assert the async dispatch.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
