feat(services): volume mounts + admin volume inventory (C1)

services.volumes JSONB [{type: volume|bind, source, target, read_only}]
mapped into every replica's container config at deploy and reconcile
time, hashed into the runtime spec so mount changes trigger
reconciliation. Mounted via existing docker.HostConfig.Mounts.

- RuntimeSpec.Volumes + specHash + mount.Mount mapping in createReplica
- Create/update service accepts volumes; PUT replaces the whole list
- Replica-count reconcile now goes through the deploy queue — the last
  raw `go` reconcile left that could race a build
- GET /admin/volumes inventories node volumes with in_use flags;
  DELETE /admin/volumes/:name removes unused ones (409 on in-use)
- CLI: services update --volume/--bind/--clear-volumes, volumes
  list|delete; MCP: services_update + volumes_list/delete
- Settings UI: Volumes section with mount editor
- Migration normalizes the nullable baseline column to NOT NULL [].

Verified live: deploy applies mounts to the container, docker
auto-creates named volumes, in-use deletion is refused.

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

app/backend/internal/cli/commands/volumes.go

@@ -0,0 +1,71 @@
+package commands
+
+import (
+	"fmt"
+
+	"github.com/spf13/cobra"
+)
+
+// VolumesCmd manages docker volumes on the node (admin).
+var VolumesCmd = &cobra.Command{
+	Use:     "volumes",
+	Aliases: []string{"volume"},
+	Short:   "Manage docker volumes (admin)",
+}
+
+var volumesListCmd = &cobra.Command{
+	Use:   "list",
+	Short: "List docker volumes with in-use flags",
+	Args:  cobra.NoArgs,
+	RunE: func(cmd *cobra.Command, args []string) error {
+		c, err := client()
+		if err != nil {
+			return err
+		}
+		data, err := c.Do("GET", "/admin/volumes", nil)
+		if err != nil {
+			return err
+		}
+		items, err := unwrapList(data, "volumes")
+		if err != nil {
+			return err
+		}
+		rows := make([][]string, 0, len(items))
+		for _, v := range items {
+			inUse := "no"
+			if b, ok := v["in_use"].(bool); ok && b {
+				inUse = "yes"
+			}
+			rows = append(rows, []string{str(v, "name"), str(v, "driver"), inUse})
+		}
+		printRows(data, []string{"NAME", "DRIVER", "IN USE"}, rows)
+		return nil
+	},
+}
+
+var volumesDeleteCmd = &cobra.Command{
+	Use:   "delete <name>",
+	Short: "Delete an unused docker volume",
+	Args:  cobra.ExactArgs(1),
+	RunE: func(cmd *cobra.Command, args []string) error {
+		c, err := client()
+		if err != nil {
+			return err
+		}
+		if !Confirm(fmt.Sprintf("Delete volume %s?", args[0])) {
+			return &APIError{Message: "aborted (pass --yes to skip confirmation)", ExitCode: ExitError}
+		}
+		if _, err := c.Do("DELETE", "/admin/volumes/"+args[0], nil); err != nil {
+			return err
+		}
+		if JSONMode() {
+			return PrintJSON(map[string]string{"status": "deleted", "name": args[0]})
+		}
+		fmt.Printf("Deleted volume %s\n", args[0])
+		return nil
+	},
+}
+
+func init() {
+	VolumesCmd.AddCommand(volumesListCmd, volumesDeleteCmd)
+}