fix: remove immediate foreground terminal bypass

[nwparker]

Summary

• Removes the Speed up visible terminal output floods #4039 foreground isLatencySensitiveForegroundOutput bypass instead of keeping the additive rolling budget from fix: stop OpenTUI redraw and git polling freezes #4585.
• Visible foreground PTY output now uses the existing scheduler by default; hidden/startup output keeps the latency-sensitive path.
• Net effect on production code: pty-connection.ts deletes the immediate foreground classifier and routes foreground PTY bytes through the scheduler.

Diagnosis

I did not complete a true historical bisect before merging #4585. That PR fixed the repros, but it stacked a budget on top of the suspect code. This follow-up narrows the bad code more directly.

Controlled replay results on a diagnosis branch:

• Current main with fix: stop OpenTUI redraw and git polling freezes #4585 reverted failed the captured OpenCode replay:
  • maxTimerDrift=925.4ms foregroundWrites=74063 deferredForegroundEnqueues=0
• Reverting all of Speed up visible terminal output floods #4039 (2c8bbacca1d775353db44dad72127aa2f38bbfcf, perf: batch visible terminal output floods) conflicts through later terminal work and also removes the scheduler itself, which is not the minimal safe change.
• Deleting only Speed up visible terminal output floods #4039's immediate foreground classifier while keeping the scheduler passes the captured replay:
  • maxTimerDrift=375.8ms foregroundWrites=74063 deferredForegroundEnqueues=74063

So the bad hunk is #4039's immediate foreground bypass for <=2KB chunks / recent ANSI redraws, not the scheduler machinery as a whole.

Refs #4039, #4558, #4559, #4581, #4585.

Test plan

Rebased on origin/main at 843d969c7d; branch head bc424c9217.

• pnpm exec vitest run --config config/vitest.config.ts src/renderer/src/components/terminal-pane/pty-connection.test.ts src/main/git/status-upstream-probe-churn.test.ts
  • Passed: 116 tests
• pnpm typecheck
• pnpm exec oxfmt --check src/renderer/src/components/terminal-pane/pty-connection.ts src/renderer/src/components/terminal-pane/pty-connection.test.ts
• pnpm exec oxlint src/renderer/src/components/terminal-pane/pty-connection.ts src/renderer/src/components/terminal-pane/pty-connection.test.ts
• pnpm test
  • Passed: 13,550 tests; 11 skipped
• npx playwright test tests/e2e/terminal-foreground-redraw-freeze.spec.ts --config tests/playwright.config.ts --project electron-headless -g "captured OpenCode/OpenTUI" --reporter=json > .tmp/simplify-rebased-terminal-captured.json
  • Passed: elapsed=363.9ms maxTimerDrift=334.1ms samples=1 foregroundWrites=74063 deferredForegroundEnqueues=74063 deferredForegroundWrites=1 scheduledDrains=2
• SKIP_BUILD=1 npx playwright test tests/e2e/terminal-foreground-redraw-freeze.spec.ts --config tests/playwright.config.ts --project electron-headless -g "active OpenTUI-style" --reporter=json > .tmp/simplify-rebased-terminal-synthetic.json
  • Passed: elapsed=34.8ms maxTimerDrift=2.7ms samples=2 foregroundWrites=270 deferredForegroundEnqueues=270 deferredForegroundWrites=11 scheduledDrains=1
• SKIP_BUILD=1 npx playwright test tests/e2e/git-no-upstream-polling-churn.spec.ts --config tests/playwright.config.ts --project electron-headless --reporter=json > .tmp/simplify-rebased-git-polling.json
  • Passed: elapsed=7201.8ms maxTimerDrift=4.2ms samples=450 noUpstreamFailures=1 missingOriginFailures=1

[nwparker]

Closing as superseded by a better bounded design: #4585 shipped a rolling immediate-output budget and #7214 refined the scheduler. Current main deliberately preserves bounded input-latency handling; removing the classifier wholesale would regress it.