Host detail v2: full pipeline + per-stage logs + WoL diagnostics

Pipeline now always renders all 13 nodes (3 pre-stage + 9 stage +
Completed), synthesising ghosts from run state when stage rows
aren't seeded yet. Makes a WaitingWoL host show the full timeline
ahead of it instead of just 4 dots.

Agent tags each log line with its stage; logs.Hub fans out to both
log-{runID} and log-{runID}-{stage} SSE events so the detail page
can show per-stage tabs with a pure-CSS radio-sibling switch. Flat
run log prepends [stage] so grep still works.

Dispatcher writes picked/sent-WoL/heartbeat lines into the per-run
log — the operator opens the detail page, sees WaitingWoL stuck,
and reads exactly what the dispatcher did and why nothing's
progressing, instead of having to tail journalctl on the LXC.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

internal/web/templates/pipeline_test.go

@@ -36,9 +36,10 @@ func seedStages() []model.Stage {
 
 func TestBuildPipeline_NoRun(t *testing.T) {
 	nodes := BuildPipeline(nil, nil)
-	if len(nodes) != len(preStageOrder)+1 {
-		// No stage rows = just pre-stages + Completed.
-		t.Fatalf("len = %d, want %d", len(nodes), len(preStageOrder)+1)
+	// Ghost pipeline: 3 pre-stages + 9 stage ghosts + 1 terminal = 13
+	// nodes, all pending.
+	if len(nodes) != 13 {
+		t.Fatalf("len = %d, want 13", len(nodes))
 	}
 	for i, n := range nodes {
 		if n.State != "pending" {
@@ -47,6 +48,57 @@ func TestBuildPipeline_NoRun(t *testing.T) {
 	}
 }
 
+// TestBuildPipeline_GhostStagesBeforeClaim models the real WaitingWoL
+// case: the run exists but agent hasn't called /claim yet, so there are
+// no stage rows. Pipeline must still render all 9 stage nodes as ghosts
+// so the operator sees the full timeline ahead of them.
+func TestBuildPipeline_GhostStagesBeforeClaim(t *testing.T) {
+	run := &model.Run{State: model.StateWaitingWoL}
+	nodes := BuildPipeline(run, nil)
+	if len(nodes) != 13 {
+		t.Fatalf("len = %d, want 13", len(nodes))
+	}
+	if nodes[idxQueued].State != "passed" {
+		t.Errorf("Queued = %q, want passed", nodes[idxQueued].State)
+	}
+	if nodes[idxWaitingWoL].State != "running" {
+		t.Errorf("WaitingWoL = %q, want running", nodes[idxWaitingWoL].State)
+	}
+	// All 9 stage ghosts must be pending — nothing has started yet.
+	for i := idxInventory; i <= idxReporting; i++ {
+		if nodes[i].State != "pending" {
+			t.Errorf("%s (ghost) = %q, want pending", nodes[i].Name, nodes[i].State)
+		}
+	}
+	if nodes[idxCompleted].State != "pending" {
+		t.Errorf("Completed = %q, want pending", nodes[idxCompleted].State)
+	}
+}
+
+// TestBuildPipeline_GhostStagesDuringStage models the in-flight case
+// with only some stage rows seeded: later stages must still appear as
+// pending ghosts rather than silently disappearing.
+func TestBuildPipeline_GhostStagesDuringStage(t *testing.T) {
+	run := &model.Run{State: model.StateSMART}
+	// Only Inventory + SpecValidate seeded; SMART onwards are ghosts.
+	stages := []model.Stage{
+		{Name: "Inventory", Ordinal: 0, State: model.StagePassed},
+		{Name: "SpecValidate", Ordinal: 1, State: model.StagePassed},
+	}
+	nodes := BuildPipeline(run, stages)
+	if len(nodes) != 13 {
+		t.Fatalf("len = %d, want 13", len(nodes))
+	}
+	if nodes[idxSMART].State != "running" {
+		t.Errorf("SMART (ghost) = %q, want running", nodes[idxSMART].State)
+	}
+	for _, i := range []int{idxCPUStress, idxStorage, idxNetwork, idxGPU, idxPSU, idxReporting} {
+		if nodes[i].State != "pending" {
+			t.Errorf("%s (ghost) = %q, want pending", nodes[i].Name, nodes[i].State)
+		}
+	}
+}
+
 func TestBuildPipeline_Running(t *testing.T) {
 	run := &model.Run{State: model.StateSMART}
 	stages := seedStages()