fix: preserve stopped terminal state across restarts

[hyudryu]

Summary

• tolerate direct PTY exits racing renderer reattachment
• persist stopped panes and durably checkpoint their final output before exit acknowledgement
• clean exact Windows host generations without respawning shells, while retaining bounded mobile stopped frames
• preserve fallback scrollback before generation-bound snapshots when workspace storage is constrained

Validation

• node --test test/session-reattach.test.cjs test/mobile-sidebar-performance.test.cjs test/windows-pty-persistence.test.cjs test/workspace.test.js (64 passed)
• npm test -- --test-reporter=dot (430 passed)
• npm run build:web (passed; existing chunk-size warning only)
• node --check on touched JavaScript and CommonJS files
• git diff --check

Follow-up for the three post-merge Codex findings on #29.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-03T03:28:46.062554Z	d627f75	New commits

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[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: 1a6ccd0973

ℹ️ About Codex in GitHub

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