fix(file-tools): ensure OS-agnostic sensitive path protection

[Junass1]

Summary

Normalize _check_sensitive_path() comparisons so sensitive POSIX targets stay blocked even when Hermes is running on a Windows host.

Problem

_check_sensitive_path() compared realpath() / normpath() output directly against POSIX-sensitive prefixes and exact paths such as:

• /private/etc/
• /private/var/
• /var/run/docker.sock

On Windows hosts, those path helpers can produce backslash-normalized paths, which makes direct string comparisons host-OS dependent and risks missing sensitive POSIX targets.

Fix

• Add a small path normalizer that:
  • expands ~
  • normalizes the path
  • converts backslashes to forward slashes
  • strips trailing slashes consistently
• Use that normalized form for both resolved and literal-path comparisons in _check_sensitive_path()

Tests

Added regression coverage for Windows-host semantics by monkeypatching realpath() / normpath() to return backslash-normalized paths and verifying that:

• /var/run/docker.sock is still blocked
• /private/etc/hosts is still blocked
• /tmp/safe_file.txt is still allowed

Verification

Passed locally via:

• uv run pytest tests/tools/test_file_write_safety.py -q
• uv run pytest tests/tools/test_write_deny.py -q

[alt-glitch]

Related to #4993 — both address cross-platform path guard bypass where backslash-normalized paths on Windows skip POSIX-sensitive path checks in _check_sensitive_path().

[teknium1]

Thanks for identifying the Windows-sensitive-path gap. The premise still holds on current main: tools/file_tools.py:639 uses host-specific os.path.normpath, then tools/file_tools.py:644-648 compares that value directly to forward-slash POSIX literals.

Problems

• The submitted hunk predates the current resolver. _check_sensitive_path now accepts task_id and resolves via _resolve_path_for_task(filepath, task_id) at tools/file_tools.py:633-639; the old os.path.realpath-based context in this PR no longer matches current main.
• Current regression coverage at tests/tools/test_file_write_safety.py:171-196 covers POSIX/macOS spellings but not Windows-style normalization.

Suggested changes

• Reapply the normalizer to both current comparison operands without replacing the task-aware resolver.
• Port the exact-path, prefix-path, and safe-path Windows-normalization tests to the current test file.

This is an automated hermes-sweeper review.