[bugfix] Fix invalid ManagerChannel enum value in nodepack installation (#5312)

* [bugfix] Fix invalid ManagerChannel enum value in nodepack installation

Fix nodepack installation failure caused by using 'stable' channel value
which is not defined in the ManagerChannel enum. Changed from 'stable'
to 'default' which is a valid enum value according to the backend schema.

Fixes nodepack installation requests that were failing validation at
/v2/manager/queue/task endpoint.

🤖 Generated with [Claude Code](https://claude.ai/code)

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

* [refactor] Enforce type safety for enum values without type assertions

Remove type assertions (as ManagerChannel) and use explicit Record typing
to ensure compile-time validation of enum values. This prevents invalid
enum values from being used by catching them during TypeScript compilation
rather than runtime validation failures.

- Replace type assertions with Record<string, ManagerChannel> typing
- Remove manual casting that bypassed TypeScript's type checking
- Ensure invalid enum values cause compilation errors

---------

Co-authored-by: Claude <noreply@anthropic.com>

src/components/dialog/content/manager/PackVersionSelectorPopover.vue

@@ -109,15 +109,15 @@ const SelectedVersionValues = {
   NIGHTLY: 'nightly' as SelectedVersion
 }
 
-const ManagerChannelValues = {
-  STABLE: 'stable' as ManagerChannel,
-  DEV: 'dev' as ManagerChannel
+const ManagerChannelValues: Record<string, ManagerChannel> = {
+  DEFAULT: 'default', // ✅ Valid - will compile
+  DEV: 'dev' // ✅ Valid - will compile
 }
 
-const ManagerDatabaseSourceValues = {
-  CACHE: 'cache' as ManagerDatabaseSource,
-  REMOTE: 'remote' as ManagerDatabaseSource,
-  LOCAL: 'local' as ManagerDatabaseSource
+const ManagerDatabaseSourceValues: Record<string, ManagerDatabaseSource> = {
+  CACHE: 'cache',
+  REMOTE: 'remote',
+  LOCAL: 'local'
 }
 
 const { nodePack } = defineProps<{
@@ -242,7 +242,7 @@ const handleSubmit = async () => {
   await managerStore.installPack.call({
     id: nodePack.id,
     repository: nodePack.repository ?? '',
-    channel: ManagerChannelValues.STABLE,
+    channel: ManagerChannelValues.DEFAULT,
     mode: ManagerDatabaseSourceValues.CACHE,
     version: actualVersion,
     selected_version: selectedVersion.value