[BUG] semgrep plugin PostToolUse hook constructs wrong path when editing files outside CWD

Bug description

The semgrep@claude-plugins-official plugin's PostToolUse hook (hook-darwin-arm64 binary) incorrectly constructs the file path to scan when an edited file lives outside the current working directory.

Steps to reproduce

1. Open a Claude Code session in project directory A (e.g. ~/Code/project-a)
2. Edit a file in a different directory B (e.g. ~/Code/project-b/script.py) using the Edit tool
3. The semgrep PostToolUse hook fires and returns an error

Observed behaviour

The hook returns additionalContext with an error like:

open /Users/alice/Code/project-a/Users/alice/Code/project-b/script.py: no such file or directory

The path is constructed as $CWD + absolute_path_without_leading_slash, doubling the directory tree.

Expected behaviour

When tool_input.file_path is already an absolute path, it should be used directly — not prepended with $CWD.

Environment

• Plugin: semgrep@claude-plugins-official v2.0.1
• Binary: hook-darwin-arm64
• Platform: macOS (darwin arm64)
• Claude Code version: current

Confirmed via

Running the binary directly with a cross-directory Edit payload reproduces the bad path:

echo '{"tool_name":"Edit","tool_input":{"file_path":"/Users/alice/Code/project-b/script.py"},"tool_response":{"filePath":"/Users/alice/Code/project-b/script.py"}}' \
  | ~/.claude/plugins/cache/claude-plugins-official/semgrep/2.0.1/scripts/hook-darwin-arm64 claude PostToolUse
# → {"hookSpecificOutput":{"additionalContext":"open /Users/alice/Code/project-a/Users/alice/Code/project-b/script.py: no such file or directory",...}}

Workaround

Add to the project's .claude/settings.local.json:

{
  "enabledPlugins": {
    "semgrep@claude-plugins-official": false
  }
}