feat: orphan stack detection/deletion, filebrowser infra, setup scripts

- Add orphan detection: stacks not in catalog marked as "Elavult"
- Add DELETE /api/stacks/{name} endpoint with HDD data handling
- Add GET /api/stacks/{name}/hdd-data endpoint
- Add delete confirmation modal with HDD data checkbox (Hungarian UI)
- Add filebrowser to protected stacks list
- Add scripts/hdd-setup.sh and scripts/docker-setup.sh for node setup
- Hide "Frissítés" and "Részletek" buttons for orphaned stacks

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

controller/internal/stacks/manager.go

@@ -29,6 +29,7 @@ const (
 	StatePaused      ContainerState = "paused"
 	StateUnknown     ContainerState = "unknown"
 	StateNotDeployed ContainerState = "not_deployed"
+	StateOrphaned    ContainerState = "orphaned"
 )
 
 // ContainerInfo holds status info about a single container within a stack.
@@ -47,6 +48,7 @@ type Stack struct {
 	State       ContainerState  `json:"state"`
 	Deployed    bool            `json:"deployed"`    // Has app.yaml with deployed=true
 	Protected   bool            `json:"protected"`
+	Orphaned    bool            `json:"orphaned"`   // Deployed but no catalog template
 	Containers  []ContainerInfo `json:"containers"`
 	AppConfig   *AppConfig      `json:"app_config,omitempty"`
 	LastUpdated time.Time       `json:"last_updated"`
@@ -166,6 +168,25 @@ func (m *Manager) ScanStacks() error {
 		}
 	}
 
+	// Detect orphaned stacks (deployed but no longer in catalog)
+	catalogTemplates := m.getCatalogTemplateSlugs()
+	if catalogTemplates != nil {
+		orphanCount := 0
+		for _, stack := range m.stacks {
+			if stack.Protected || !stack.Deployed {
+				stack.Orphaned = false
+				continue
+			}
+			stack.Orphaned = !catalogTemplates[stack.Name]
+			if stack.Orphaned {
+				orphanCount++
+			}
+		}
+		if orphanCount > 0 {
+			m.logger.Printf("[INFO] Detected %d orphaned stack(s)", orphanCount)
+		}
+	}
+
 	deployedCount := 0
 	for _, s := range m.stacks {
 		if s.Deployed {
@@ -733,4 +754,25 @@ func (m *Manager) CommittedMemory() (requestMB int, limitMB int) {
 		limitMB += ParseMemoryMB(s.Meta.Resources.MemLimit)
 	}
 	return
+}
+
+// getCatalogTemplateSlugs reads the synced catalog cache and returns a set of
+// template slugs (directory names) that have a docker-compose.yml.
+func (m *Manager) getCatalogTemplateSlugs() map[string]bool {
+	cacheDir := filepath.Join(m.cfg.Paths.DataDir, "catalog-cache", "templates")
+	entries, err := os.ReadDir(cacheDir)
+	if err != nil {
+		m.logger.Printf("[WARN] Cannot read catalog cache for orphan detection: %v", err)
+		return nil
+	}
+	slugs := make(map[string]bool, len(entries))
+	for _, e := range entries {
+		if e.IsDir() {
+			composePath := filepath.Join(cacheDir, e.Name(), "docker-compose.yml")
+			if _, err := os.Stat(composePath); err == nil {
+				slugs[e.Name()] = true
+			}
+		}
+	}
+	return slugs
 }