Dashboard tab: CPU/mem/load, hwmon temps+fans, net, disks, filesystems, UPS with 10-min sparklines

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

cmd/hamlab/main.go

@@ -20,6 +20,7 @@ import (
 	"hamlab/internal/api"
 	"hamlab/internal/auth"
 	"hamlab/internal/config"
+	"hamlab/internal/metrics"
 	"hamlab/internal/store"
 	hterm "hamlab/internal/term"
 	"hamlab/internal/web"
@@ -136,7 +137,10 @@ func serve(cfg *config.Config) error {
 		}
 	}
 
-	srv := api.New(cfg, sessions, mgr, web.FS(), version)
+	col := metrics.NewCollector()
+	go col.Run(context.Background())
+
+	srv := api.New(cfg, sessions, mgr, col, web.FS(), version)
 	hs := &http.Server{
 		Addr:              cfg.Listen,
 		Handler:           srv.Handler(),