monitor: see unikernel VMs + use canonical container naming

Two drift-reporting bugs:
1. The monitor listed only the podman runtime, so unikernel VMs always
   showed observed=unknown (false drift). It now takes a ContainerLister
   and the agent passes a merged lister (containers + VMs), mirroring
   listAllContainers.
2. The monitor computed the lookup name as service+"-"+component, which
   is wrong when component==service (the name collapses to just the
   service, e.g. "uktest"/"mc-proxy"). It now uses the canonical
   naming.ContainerNameFor — extracted to a shared package so the agent
   and monitor can't disagree.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

internal/monitor/monitor.go

@@ -8,15 +8,23 @@ import (
 	"time"
 
 	"git.wntrmute.dev/mc/mcp/internal/config"
+	"git.wntrmute.dev/mc/mcp/internal/naming"
 	"git.wntrmute.dev/mc/mcp/internal/registry"
 	"git.wntrmute.dev/mc/mcp/internal/runtime"
 )
 
+// ContainerLister reports the observed containers on the node. A full
+// runtime.Runtime satisfies it; the agent passes a lister that merges the
+// container and unikernel runtimes so the monitor sees VMs too.
+type ContainerLister interface {
+	List(ctx context.Context) ([]runtime.ContainerInfo, error)
+}
+
 // Monitor watches container states and compares them to the registry,
 // recording events and firing alerts on drift or flapping.
 type Monitor struct {
 	db      *sql.DB
-	runtime runtime.Runtime
+	lister  ContainerLister
 	cfg     config.MonitorConfig
 	logger  *slog.Logger
 	alerter *Alerter
@@ -26,11 +34,12 @@ type Monitor struct {
 	prevState map[string]string // key: "service/component", value: observed state
 }
 
-// New creates a Monitor with the given dependencies.
-func New(db *sql.DB, rt runtime.Runtime, cfg config.MonitorConfig, nodeName string, logger *slog.Logger) *Monitor {
+// New creates a Monitor with the given dependencies. lister reports observed
+// containers (and unikernel VMs, via a merged lister).
+func New(db *sql.DB, lister ContainerLister, cfg config.MonitorConfig, nodeName string, logger *slog.Logger) *Monitor {
 	return &Monitor{
 		db:        db,
-		runtime:   rt,
+		lister:    lister,
 		cfg:       cfg,
 		logger:    logger,
 		alerter:   NewAlerter(cfg, nodeName, db, logger),
@@ -82,7 +91,7 @@ func (m *Monitor) tick() {
 	ctx := context.Background()
 
 	// Get the current runtime state of all containers.
-	containers, err := m.runtime.List(ctx)
+	containers, err := m.lister.List(ctx)
 	if err != nil {
 		m.logger.Error("monitor: list containers", "error", err)
 		return
@@ -113,7 +122,7 @@ func (m *Monitor) tick() {
 		for _, comp := range components {
 			key := comp.Service + "/" + comp.Name
 			seen[key] = struct{}{}
-			containerName := comp.Service + "-" + comp.Name
+			containerName := naming.ContainerNameFor(comp.Service, comp.Name)
 
 			observed := "unknown"
 			if state, ok := runtimeState[containerName]; ok {