Honor the user's NEVER USE APPDATA directive. The Tier 2 state and
failure report directories now default to project-relative gitignored
locations under tests/artifacts/ instead of C:\\Users\\Ed\\AppData\\.
- failcount.py: _state_dir() now defaults to
tests/artifacts/tier2_state/<track>/ (gitignored)
- write_report.py: _failures_dir() now defaults to
tests/artifacts/tier2_failures/ (gitignored)
The TIER2_STATE_DIR and TIER2_FAILURES_DIR env vars still override the
defaults when set (preserves the existing escape hatch).
ed