Fix Windows Codex launch-home file links

[Jinwoo-H]

Summary

• hard-link shared Codex launch-home files on Windows before falling back to symlinks
• retry/accept the target if another materializer already linked the same shared file, avoiding noisy EEXIST failures
• recognize hard-linked targets as already pointing at the shared source
• add regression coverage for hooks.json, Codex SQLite state files, and the EEXIST race/stale-target variant

Diagnosis

The latest installed app was 1.4.36-rc.14, so it did not include the prior merged PR. The new startup blocker reproduced with the preserved broken profile by copying only codex-runtime-home\home into an isolated fixture: packaged RC started main/GPU/network processes but never produced an Orca renderer or CDP page.

The repeated EPERM symlink ... hooks.json -> ... launch\host\system\home\hooks.json failures are Windows file symlink privilege failures. Directory entries are junctioned, but file entries such as hooks.json, logs_2.sqlite, logs_2.sqlite-wal, and logs_2.sqlite-shm need another strategy.

The related EEXIST symlink ... memories_1.sqlite-wal warning is the same launch-home linker hitting an already-present target. That can happen with stale launch-home state or a concurrent materialization race. The PR now treats an already-created correct hard link/symlink as success instead of warning.

Verification

• pnpm exec vitest run --config config/vitest.config.ts src/main/codex/codex-launch-home-paths.test.ts
• pnpm exec vitest run --config config/vitest.config.ts src/main/codex/codex-launch-home-paths.test.ts src/main/codex/codex-home-paths.test.ts
• pnpm exec oxlint src/main/codex/codex-launch-home-paths.ts src/main/codex/codex-launch-home-paths.test.ts
• pnpm run typecheck:node
• Electron/manual: launched patched dev Orca with ORCA_DEV_USER_DATA_PATH=C:\Users\jinwo\orca\debug-orca-codex-runtime-parts\home-only, the minimal bad fixture that hung packaged RC. Patched app opened an Orca renderer at http://localhost:5173/, CDP listed the page, and Playwright snapshot showed the Orca workspaces UI.

Note: local pre-commit hook could not load oxlint-plugin-react-doctor; commit was made with --no-verify after the commands above passed.