B2b: decommission orchestration + missing-storage indicator + re-enroll fix (v0.65.0)

agentapi.Decommission + handleStorageDecommission (migrate-all-or-none, Change 2):
migrate-then-decommission via the migration done-hook, or decommission-anyway (stop
apps, keep HDD_PATH). 'Hiányzó tárhely' badge on dashboard/stacks/app card when an
app's drive is decommissioned/disconnected/absent. Change 4: registerStoragePath
clears the decommissioned marker on re-enroll (ClearDecommissioned had no callers).
Non-hollow tests incl. mutation-proven Change-4 companion.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

controller/internal/web/storage_handlers_test.go

@@ -27,14 +27,15 @@ func TestTemplatesParse(t *testing.T) {
 
 // mockAgent records calls so tests can assert the refusal path performs NO mount/destructive action.
 type mockAgent struct {
-	disks        agentapi.DisksResponse
-	formatRes    agentapi.FormatResult
-	formatErr    error
-	assignErr    error
-	assignCalls  []assignCall
-	disksCalls   int
-	formatCalls  []formatCall
-	guestAttachCalls []string
+	disks             agentapi.DisksResponse
+	formatRes         agentapi.FormatResult
+	formatErr         error
+	assignErr         error
+	assignCalls       []assignCall
+	disksCalls        int
+	formatCalls       []formatCall
+	guestAttachCalls  []string
+	decommissionCalls []string
 }
 
 type assignCall struct{ uuid, where, fstype string }
@@ -58,6 +59,10 @@ func (m *mockAgent) AssignDisk(_ context.Context, uuid, where, fstype, _ string)
 func (m *mockAgent) EjectDisk(_ context.Context, where string) (agentapi.EjectResult, error) {
 	return agentapi.EjectResult{Ejected: where}, nil
 }
+func (m *mockAgent) Decommission(_ context.Context, where string) (agentapi.DecommissionResult, error) {
+	m.decommissionCalls = append(m.decommissionCalls, where)
+	return agentapi.DecommissionResult{Decommissioned: where}, nil
+}
 func (m *mockAgent) GuestAttach(_ context.Context, where string) error {
 	m.guestAttachCalls = append(m.guestAttachCalls, where)
 	return nil