Patch fstab on Cygwin temporarily

[smorimoto]

Closes #972

[Copilot]

Pull Request Overview

This PR temporarily patches the Cygwin fstab configuration to address issue #972. Key changes include:

• Adding a new function fixFstab() in windows.ts to modify the fstab file.
• Updating installer.ts to import and invoke fixFstab() after setting up the environment.
• Introducing additional file system and path modules to support the patch.

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
packages/setup-ocaml/src/windows.ts	Adds fixFstab() to patch the fstab file
packages/setup-ocaml/src/installer.ts	Imports and calls fixFstab() in the installer flow

Comments suppressed due to low confidence (1)

packages/setup-ocaml/src/windows.ts:93

• Ensure that the Node.js version in use supports lookbehind assertions in regular expressions, as used in this patch substitution. Without support, the replacement may fail at runtime.

const patchedContents = contents.replace(

[dra27]

Assuming this doesn't lead to any problems, it should be a permanent change - it brings setup-ocaml into line with how opam manages Cygwin as well (it's also philosophically correct: the opam root is a native Windows directory so it shouldn't be being manipulated with POSIX permissions)