fix(dashboards): fix broken panels from metric audit
- peer-health: convert panel 310 "chainsync event distribution" from histogram to timeseries (event_total is a CounterVec, not a Histogram; Grafana histogram panel requires _bucket data and was showing "No histogram found in response") - node-overview: remove network label filter from panel 52 go_gc_duration_seconds (Go runtime Summary registered on DefaultRegisterer, never carries the network label) - resources: remove network label filter from panel 56 go_gc_duration_seconds (same reason) - resources: fix panel 61 "Badger Block Cache Hit Ratio" — replace rate(hits/(hits+misses)) with the precomputed database_blob_block_cache_hit_ratio GaugeFunc (badger metrics are GaugeFunc on DefaultRegisterer: rate() is wrong and instance label filter returns no results) - resources: fix panel 62 "Badger Cache Hits vs Misses" — remove incorrect rate() wrapper and instance label filter from badger GaugeFunc metrics Signed-off-by: wcatz <[email protected]>