feat: persistent storage for Deno static sites

- Add storage_enabled and storage_limit_mb columns to static_sites.
- Create/attach Docker volumes (tinyforge-site-{name}-data) for Deno
  sites with storage enabled, mounted at /app/data.
- Grant --allow-write=/app/data in Deno container CMD.
- Add storage usage API endpoint (GET /api/sites/{id}/storage).
- Show storage section in site detail page with usage bar.
- Add storage toggle and limit field to new site wizard.
- Use ConfirmDialog for secret deletion instead of inline delete.

internal/staticsite/manager.go

@@ -10,6 +10,8 @@ import (
 	"strconv"
 	"time"
 
+	"github.com/moby/moby/api/types/mount"
+
 	"github.com/alexei/tinyforge/internal/crypto"
 	"github.com/alexei/tinyforge/internal/docker"
 	"github.com/alexei/tinyforge/internal/events"
@@ -198,6 +200,22 @@ func (m *Manager) Deploy(ctx context.Context, siteID string, force bool) error {
 
 	containerName := fmt.Sprintf("dw-site-%s", site.Name)
 
+	// Prepare volume mounts for persistent storage.
+	var mounts []mount.Mount
+	if site.StorageEnabled && mode == "deno" {
+		volName, volErr := m.docker.EnsureSiteVolume(ctx, site.Name)
+		if volErr != nil {
+			slog.Warn("static site: failed to ensure storage volume", "site", site.Name, "error", volErr)
+		} else {
+			mounts = append(mounts, mount.Mount{
+				Type:   mount.TypeVolume,
+				Source: volName,
+				Target: "/app/data",
+			})
+			slog.Info("static site: storage volume attached", "site", site.Name, "volume", volName)
+		}
+	}
+
 	// Create and start new container.
 	containerID, err := m.docker.CreateContainer(ctx, docker.ContainerConfig{
 		Name:         containerName,
@@ -206,6 +224,7 @@ func (m *Manager) Deploy(ctx context.Context, siteID string, force bool) error {
 		ExposedPorts: []string{containerPort + "/tcp"},
 		NetworkName:  networkName,
 		NetworkID:    networkID,
+		Mounts:       mounts,
 		Labels: map[string]string{
 			"tinyforge.static-site":    site.ID,
 			"tinyforge.static-site-name": site.Name,
@@ -229,6 +248,7 @@ func (m *Manager) Deploy(ctx context.Context, siteID string, force bool) error {
 			ExposedPorts: []string{containerPort + "/tcp"},
 			NetworkName:  networkName,
 			NetworkID:    networkID,
+			Mounts:       mounts,
 			Labels: map[string]string{
 				"tinyforge.static-site":    site.ID,
 				"tinyforge.static-site-name": site.Name,
@@ -346,6 +366,13 @@ func (m *Manager) Remove(ctx context.Context, siteID string) error {
 		}
 	}
 
+	// Remove storage volume if it was enabled (best effort).
+	if site.StorageEnabled {
+		if err := m.docker.RemoveSiteVolume(ctx, site.Name); err != nil {
+			slog.Warn("static site: failed to remove storage volume", "site", site.Name, "error", err)
+		}
+	}
+
 	return nil
 }