Configuration State Metrics

[ev-shindin]

Expose current configuration as metrics so operators can verify settings without checking ConfigMaps.

Metrics:

wva_config_info                     gauge   {analyzer_name, limiter_enabled, scale_to_zero_enabled}
wva_config_kv_spare_threshold       gauge   {}
wva_config_queue_spare_threshold    gauge   {}
wva_config_optimization_interval_seconds  gauge {}

Implementation:

• Emit on each optimization cycle (values may change via ConfigMap hot-reload)
• Use prometheus.NewGaugeVec with const labels pattern for wva_config_info

Acceptance Criteria:

• Config info gauge reflects current analyzer and feature flags
• Threshold gauges update when ConfigMap changes
• Unit tests verify metric values match config