feat(group): add node group management UI

Add node group management interface with automatic user assignment and traffic-based grouping.

Features:
- Node group CRUD with traffic range configuration
- Three grouping modes: average, subscription-based, and traffic-based
- Group recalculation with preview and history tracking
- Subscribe-to-group mapping management
- User subscription group locking
- Group calculation history with detailed reports
- Multi-language support (en-US, zh-CN)
- Enhanced node and subscription forms with group selection

apps/admin/public/assets/locales/en-US/product.json

@@ -1,4 +1,5 @@
 {
+  "all": "All",
   "cancel": "Cancel",
   "confirm": "Confirm",
   "confirmDelete": "Are you sure you want to delete?",
@@ -7,13 +8,16 @@
   "create": "Create",
   "createSubscribe": "Create Subscription",
   "createSuccess": "Create Successful",
+  "currentUserGroup": "Current User Group",
+  "defaultNodeGroup": "Default Node Group",
   "delete": "Delete",
+  "nodeGroups": "Node Groups",
+  "nodes": "nodes",
   "deleteSuccess": "Delete Successful",
   "deleteWarning": "Data cannot be recovered after deletion. Please proceed with caution.",
   "deviceLimit": "IP Limit",
   "edit": "Edit",
   "editSubscribe": "Edit Subscription",
-  "sortSuccess": "Sort completed successfully",
   "form": {
     "annualReset": "Annual Reset",
     "basic": "Basic",
@@ -30,7 +34,6 @@
     "discountPercent": "Discount Percentage",
     "Hour": "Hour",
     "inventory": "Subscription Limit",
-    "unlimitedInventory": "Unlimited (enter -1)",
     "language": "Language",
     "languageDescription": "Leave empty for default without language restriction",
     "languagePlaceholder": "Language identifier for the subscription, e.g., en-US, zh-CN",
@@ -40,7 +43,19 @@
     "name": "Name",
     "node": "Node",
     "nodeGroup": "Node Group",
-    "nodes": "Nodes",
+    "nodeGroups": "Node Groups",
+    "nodeGroupsDescription": "Assign this product to multiple node groups. Users will get nodes from these groups.",
+    "nodeGroupsFirstSelectionDescription": "Select node groups for this product. The first selected group will be set as the default node group.",
+    "defaultNodeGroup": "Default Node Group",
+    "defaultNodeGroupDescription": "Select the default node group for this product. This will be automatically included in the backup node groups.",
+    "selectDefaultNodeGroup": "Select a default node group...",
+    "noDefaultNodeGroup": "No Default Node Group",
+    "backupNodeGroups": "Backup Node Groups",
+    "backupNodeGroupsDescription": "Select additional backup node groups. The default node group is automatically included.",
+    "nodes": "Linked Nodes",
+    "nodesDescription": "Select nodes for this subscription",
+    "nodesInGroup": "Nodes in this group:",
+    "nodesWithoutGroupsDescription": "Nodes without group assignment will be shown here (nodes that belong to groups are managed in the Node Groups section above)",
     "noLimit": "No Limit",
     "NoLimit": "No Limit",
     "noReset": "No Reset",
@@ -61,16 +76,42 @@
     "traffic": "Traffic",
     "unitPrice": "Unit Price",
     "unitTime": "Unit Time",
+    "unlimitedInventory": "Unlimited (enter -1)",
     "Year": "Year"
   },
+  "groupMapping": "Group Mapping",
+  "groupMappingTitle": "Group Mapping",
+  "groupMappingUpdateFailed": "Failed to update group mapping",
+  "groupMappingUpdateSuccess": "Group mapping updated successfully",
+  "migrateUsers": "Migrate Users",
+  "migrateUsersTitle": "Migrate Users",
+  "migrateUsersDescription": "Migrate all users from the current user group to another group",
+  "migrateUsersWarning": "This will migrate {count} users from \"{group}\" to the target group. This action cannot be undone.",
+  "migrateUsersSuccess": "Successfully migrated {count} users to the target group",
+  "migrateUsersFailed": "Failed to migrate users",
+  "targetUserGroup": "Target User Group",
+  "selectTargetGroup": "Select a target group...",
+  "selectTargetGroupFirst": "Please select a target group first",
+  "cannotMigrateToSameGroup": "Cannot migrate to the same group",
+  "noSourceGroup": "No source group available",
+  "selectedGroup": "Selected Group",
+  "userCount": "User Count",
+  "migrating": "Migrating...",
   "inventory": "Subscription Limit",
   "language": "Language",
+  "loading": "Loading...",
   "name": "Name",
+  "noMapping": "No mapping set",
+  "noNodes": "No nodes in this group",
   "quota": "Purchase Limit/Time",
   "replacement": "Reset Price/Time",
+  "save": "Save",
+  "selectGroupPlaceholder": "Select a group...",
+  "selectUserGroup": "Select User Group",
   "sell": "Sell",
   "show": "Display",
   "sold": "Subscription Count",
+  "sortSuccess": "Sort completed successfully",
   "traffic": "Traffic",
   "unitPrice": "Unit Price",
   "updateSuccess": "Update Successful"