fix(desktop): batch PTY output to prevent bun dev crashes in terminal

[Kitenite]

Summary

• Replace setImmediate with a 16ms setTimeout for PTY output flushing, coalescing rapid TUI redraws into coherent ~60fps frames instead of flooding the renderer with tiny per-turn frames
• Extract workspaceRunRestartCommand computation outside the ref assignment in Terminal.tsx for clarity

Test plan

• Run bun dev in the desktop terminal and verify it no longer crashes
• Confirm interactive terminal echo still feels responsive (no perceptible lag from the 16ms batching)
• Test TUI apps (e.g. htop, vim) render correctly without flickering

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Summary by cubic

Batch PTY output every 16ms (~60fps) to stop flooding the renderer and fix crashes in the desktop terminal when running bun dev. Also moved workspaceRunRestartCommand computation out of the ref assignment in Terminal.tsx for clarity.

^{Written for commit b119527. Summary will update on new commits.}

Summary by CodeRabbit

• Refactor
  • Optimized terminal output batching with improved flush interval timing for better performance
  • Refactored workspace run pane restart command initialization for cleaner configuration handling

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 5feab2c9-4b6d-4454-9971-1fcbc7282ad2

📥 Commits

Reviewing files that changed from the base of the PR and between 28d58d6 and b119527.

📒 Files selected for processing (2)

• apps/desktop/src/main/terminal-host/pty-subprocess.ts
• apps/desktop/src/renderer/screens/main/components/WorkspaceView/ContentView/TabsContent/Terminal/Terminal.tsx

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📝 Walkthrough

Walkthrough

The PR modifies PTY output batching by switching from event-loop-based flushing via setImmediate() to timer-based flushing with a fixed 16ms interval, while preserving immediate and size-based flush behaviors. Additionally, terminal restart command construction is refactored to compute workspace-run commands separately with null-coalescing fallback logic.

Changes

Cohort / File(s)	Summary
PTY Output Flushing apps/desktop/src/main/terminal-host/pty-subprocess.ts	Changed output batching flush mechanism from setImmediate() to setTimeout(..., OUTPUT_FLUSH_INTERVAL_MS) with new constant OUTPUT_FLUSH_INTERVAL_MS = 16, altering burst coalescing from callback-cycle boundary to fixed timer interval.
Terminal Restart Command apps/desktop/src/renderer/screens/main/components/.../Terminal/Terminal.tsx	Refactored defaultRestartCommandRef.current construction to compute workspaceRunRestartCommand separately when in workspace-run pane mode, replacing inline ternary with null-coalescing fallback logic.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Poem

🐰 A timer ticks, sixteen swift hops,
No more racing on event-loop stops,
Commands flow smooth, restart commands shine,
With fallback logic, everything's fine!

🚥 Pre-merge checks | ✅ 2 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately describes the main change: replacing setImmediate with a timed flush to fix PTY output batching and prevent crashes.
Description check	✅ Passed	The description covers the key changes and includes a test plan, but lacks formal sections from the template (Type of Change, Testing details, Related Issues).

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✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch bun-dev-crashing-in-terminal-pty-issue

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[cubic-dev-ai]

No issues found across 2 files

[github-actions]

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