Document the ca-system-watchdog continuous monitoring agent:
- All 12 audit descriptions with severity levels and detection patterns
- Session introspection via OpenCode Server API (Audits 6, 11, 12)
- Finding severity table and action dispatch table
- Health reporting format and configuration parameters
- Constraints and related documentation links
Add System Watchdog entry to mkdocs.yml Development nav section.
Covers commits 8c13e63c and 77427bd7 (system watchdog introduction
and deep session introspection enhancement).
freemo