Fix MacOS CI

[jbx81-1337]

fixing macos ci...

[Copilot]

Pull request overview

This PR updates the fs_mkdir implementation to be safer on macOS/clang by reducing unsafe string formatting and centralizing buffer sizing for path construction.

Changes:

• Introduces a single computed max buffer length (base_max_len) for base_dir/tmp allocations.
• Replaces sprintf calls with bounded snprintf when building intermediate directory paths.

Impact Analysis:

• Blast radius: medium—affects directory-creation behavior for the stdapi filesystem “mkdir” handler and any downstream callers that rely on it; exact external consumers Unknown from diff.
• Data and contract effects: no schema/payload changes identified; behavior can change on edge-case paths (e.g., root/empty components) and for very long paths if sizing/truncation occurs.
• Rollback and test focus: easy rollback (single function change); validate mkdir with absolute + relative paths, nested paths, trailing slashes, and the "/" edge case.

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[Copilot]

Pull request overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated 1 comment.

[Copilot]

Pull request overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated 1 comment.