fix: distinguish phase file writes from reads in PostToolUse hook
- Parse tool_name via jq: Write tool checks file_path match,
Bash tool checks for redirect operator (>) with phase file path
- Reads (cat, head) no longer trigger false-positive markers
- Split guard into separate statements for clarity
- Move marker cleanup inside hook-install guard
- Expand tests: 5 cases covering Bash write, Write tool, Bash read,
unrelated Bash, and Write to different file
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
809dd93c3b