Add 97 test cases for four utility functions in monitor.go:
- stringValue (30 cases): Type-to-string conversion for various Go types
including string, int types, float types, json.Number, fmt.Stringer
- anyToInt64 (34 cases): Interface-to-int64 conversion with overflow
handling, string parsing, and json.Number support
- parseInterfaceStat (15 cases): Interface stat map parsing for network
interface statistics
- extractGuestOSInfo (18 cases): QEMU guest agent OS info extraction
with fallback logic for various Linux distros, Windows, FreeBSD
Coverage for these functions: 0% → 100%
Package coverage: 37.5% → 38.5%
fb240c2d40