refactor(database): make DBListFrpcInstances able to list all users' frpc instances but not single user

feat(frpcAct): user will get createdBy when query frpc instances on current server
docs(api): update related api documentation

docs/api.md

@@ -642,7 +642,7 @@ Modify system-level settings such as instance name, boot-at-start configuration,
 **Auth Required:** Yes (token)  
 **Permission Level:** Admin
 
-Retrieve a list of all frpc instances.
+Retrieve a list of all frpc instances on the server.
 
 **Request Headers:**
 ```
@@ -662,6 +662,7 @@ X-Timestamp: 1704067200000
   "message": "instances retrieved successfully",
   "data": [
     {
+      "instanceID": 1,
       "name": "my_frpc",
       "serverAddr": "127.0.0.1",
       "serverPort": "7000",
@@ -669,7 +670,8 @@ X-Timestamp: 1704067200000
       "bootAtStart": true,
       "runUser": "root",
       "configPath": "./configs/superfrpc_user_my_frpc.toml",
-      "createdAt": "2024-01-01T00:00:00Z"
+      "createdAt": "2024-01-01T00:00:00Z",
+      "createdBy": "admin"
     }
   ]
 }
@@ -682,16 +684,31 @@ X-Timestamp: 1704067200000
   "message": "instances retrieved successfully",
   "data": [
     {
+      "instanceID": 1,
       "name": "my_frpc",
       "bootAtStart": true,
       "runUser": "root",
       "configPath": "./configs/superfrpc_user_my_frpc.toml",
-      "createdAt": "2024-01-01T00:00:00Z"
+      "createdAt": "2024-01-01T00:00:00Z",
+      "createdBy": "admin"
     }
   ]
 }
 ```
 
+| Field | Type | Description |
+|-------|------|-------------|
+| instanceID | int | Instance ID |
+| name | string | Instance name |
+| serverAddr | string | frps server address (admin/superuser only) |
+| serverPort | string | frps server port (admin/superuser only) |
+| auth_method | string | Authentication method (admin/superuser only) |
+| bootAtStart | bool | Auto-start on system boot |
+| runUser | string | User to run the frpc instance as |
+| configPath | string | Path to the configuration file |
+| createdAt | string | Instance creation time (ISO 8601 format) |
+| createdBy | string | Username of the user who created this instance |
+
 > Note: Visitor users do not see sensitive information (serverAddr, serverPort, auth_method).
 
 ---