Fix macOS warm-start recording finalization

[webadderall]

Description

Fix macOS recordings that could leave a zero-byte MP4 after the countdown warm-start pause/resume. Also improve the stop-button visual and idle HUD click-through behavior.

Motivation

Audio could deliver the first post-resume sample before video and consume the shared timestamp adjustment. The following video timestamp could then move backwards, causing AVAssetWriter to fail and leave an empty recording. The idle HUD padding also intercepted clicks outside the visible controls.

Type of Change

• New Feature
• Bug Fix
• Refactor / Code Cleanup
• Documentation Update
• Other (please specify)

Related Issue(s)

None.

Screenshots / Video

Not attached. The stop control is now a filled white square inside the existing red circular recording button.

Testing Guide

1. Start a screen recording on macOS with the countdown enabled.
2. Stop the recording and confirm the editor opens a non-empty, playable MP4.
3. With no recording active, click immediately below/outside the visible HUD and confirm the click passes through.
4. During recording, confirm the stop control remains clickable.

Automated validation:

• 1,015 Vitest tests passed
• TypeScript typecheck passed
• Swift typecheck passed
• arm64 and x64 macOS native helpers rebuilt successfully

Checklist

• I have performed a self-review of my code.
• I have added any necessary screenshots or videos.
• I have linked related issue(s) and updated the changelog if applicable.

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No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Pro Plus

Run ID: 699fbb29-f180-4a35-ac11-5b4218a2f0f9

📥 Commits

Reviewing files that changed from the base of the PR and between b937f71 and 8378342.

📒 Files selected for processing (9)

• electron/native/ScreenCaptureKitRecorder.swift
• electron/native/ScreenCaptureKitRecorder.test.ts
• electron/native/bin/darwin-arm64/recordly-screencapturekit-helper
• electron/native/bin/darwin-x64/recordly-screencapturekit-helper
• src/components/launch/LaunchWindow.module.css
• src/components/launch/LaunchWindow.tsx
• src/components/launch/RecordingControls.tsx
• src/components/launch/hooks/useLaunchHudInteractionState.ts
• src/hooks/useScreenRecorder.ts

Included review availability: Your plan provides up to 10 included reviews per hour; 9 remain after this review.

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📝 Walkthrough

Walkthrough

The recorder now rejects non-monotonic timestamps and anchors resumed audio to the first post-resume video sample. The launch HUD updates pointer handling and timing. The stop control uses a styled native button. Diagnostics require a non-empty output file.

Changes

Recording and launch behavior

Layer / File(s)	Summary
Capture timestamp integrity electron/native/ScreenCaptureKitRecorder.swift, electron/native/ScreenCaptureKitRecorder.test.ts	The recorder tracks and resets per-track timestamps, rejects non-increasing video and audio samples, anchors resumed audio to video, and tests these behaviors.
Launch controls and HUD interaction src/components/launch/LaunchWindow.tsx, src/components/launch/LaunchWindow.module.css, src/components/launch/RecordingControls.tsx, src/components/launch/hooks/useLaunchHudInteractionState.ts	The HUD delegates pointer handling to its bar, uses immediate mouse-ignore actions, and renders the stop control with a styled native button.
Recording output diagnostics src/hooks/useScreenRecorder.ts	Diagnostics include the output path only when the recorded file size is greater than zero.

Estimated code review effort: 3 (Moderate) | ~20 minutes

Merge Risk: ⚪ Minimal · up to 83783

The PR is merge-ready after normal checks and review; no actionable merge-blocking risk remains.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Docstring Coverage	✅ Passed	Docstring check was indeterminate for this PR — some files could not be analyzed in time. Not blocking.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Title check	✅ Passed	The title clearly summarizes the primary macOS warm-start recording finalization fix.
Description check	✅ Passed	The description covers the purpose, motivation, change type, testing steps, validation results, and checklist status.

✨ 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 codex/macos-recording-resume-fix

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[webadderall]

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