Fix: Robust Cross-Platform Fallback for Git Hook Linking in [link-hooks.mjs](cci:7://file:///d:/Github/TypeScript/scripts/link-hooks.mjs:0:0-0:0)

[mohiuddin-khan-shiam]

Previously, scripts/link-hooks.mjs attempted to install git hooks using fs.linkSync to create hard links from the source-controlled hook scripts into .git/hooks. However, this approach fails on Windows in several common scenarios, such as:

• When the repository is on a FAT/FAT32 drive (no hard link support)
• When the working copy and .git are on different volumes (EXDEV)
• When the user lacks the required privileges (EPERM)

This prevented contributors on such systems from setting up the required git hooks, blocking or complicating development and contribution.

This PR adds a robust fallback:

• The script first tries to create a hard link as before.
• If it fails with EXDEV or EPERM, it falls back to copying the hook file using fs.copyFileSync, ensuring the hook is still installed and functional.
• All other errors are still thrown to avoid masking real issues.

This change makes npm run setup-hooks reliable on all platforms, improving the onboarding and contribution experience for Windows and cross-device users, while still preferring hard links where possible to keep hooks in sync.

Summary:
Gracefully fall back to copying git hook scripts if hard-linking fails, ensuring contributors on all platforms can set up hooks without errors.

[typescript-bot]

This PR doesn't have any linked issues. Please open an issue that references this PR. From there we can discuss and prioritise.

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I'm sorry, but none of the above is correct.