feat: add scripts/diagnose.sh — system diagnostic & recovery tool
Read-only health check (no args) or auto-fix mode (--fix):
- Service: active state, crash loop detection, recent log
- Hardware: OBD USB adapter (/dev/ttyUSBx), SIM868 UART (/dev/serial0),
dashcam USB mount, permissions
- Network: hotspot IP, web UI reachability, internet, upload server
- Storage: disk usage, SQLite integrity check, row counts, upload backlog,
log file size
- OBD status: parsed from log (last connect/disconnect/speed/errors)
- Python env: venv present, key packages importable
- Pi health: throttling flags decoded, CPU temp, free memory
- Manual recovery command cheatsheet printed at the end
Exit code = number of critical issues found (0 = healthy).
Co-authored-by: Copilot <[email protected]>
