Added comprehensive documentation for orphaned process verification:
- Detailed explanations for three default process patterns:
* pdftract mcp (MCP server subprocess)
* TH-0 (test harness - hyphen variant)
* TH_0 (test harness - underscore variant)
- Each pattern includes:
* What it is and when it appears
* Typical spawn patterns
* Why it orphans (root causes)
* Detection examples with expected output
* Manual cleanup commands
- Manual verification walkthrough with 4 scenarios:
* After a test run (normal workflow)
* Before starting a test run (pre-flight check)
* Investigating a leaking test (binary search)
* CI post-test verification (automation)
- 5 common orphan scenarios with symptoms, verification, and fixes:
* Test timeout leaves children alive
* Panic before cleanup
* Undrained Stdio::piped() blocks wait()
* Port already in use from previous run
* Fuzz harness leaves target processes
All examples include realistic command-line output and reference existing
cleanup patterns (OrphanedProcessGuard, RAII).
Verification: notes/bf-vnx45a.md
Closes bf-vnx45a
8b711f182f