fix: normalize sticky disk mount paths

[adityamaru]

Summary

• Normalize sticky disk paths before saving action state so ~ mounts are unmounted and committed correctly.
• Keep workspace-local nested mount parents writable, fixing tools like Nx that recreate .nx/cache.
• Add focused tests for path normalization and workspace parent ownership decisions.

Test plan

• npm run lint
• npm test
• npm run build

Made with Cursor

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