refactor(api): simplify instance management endpoints

- Change delete endpoint to use request body instead of path parameter
- Modify endpoint now takes field as path parameter and instance name in body
- Update README to reflect API changes
- Remove unused description field from software info
- Fix error message in auth token lookup

README.md

@@ -206,7 +206,7 @@ All API responses are returned in JSON format:
 
 ### 4. Delete frpc Instance
 
-**Endpoint:** `/frpcAct/instanceMgr/{instanceName}/delete`  
+**Endpoint:** `/frpcAct/instanceMgr/delete`  
 **Method:** POST  
 **Content-Type:** application/json  
 **Auth Required:** Yes (token)
@@ -214,6 +214,7 @@ All API responses are returned in JSON format:
 **Request:**
 ```json
 {
+  "instanceName": "my_frpc",
   "token": "your_token",
   "timeStamp": 1704067200000
 }
@@ -234,7 +235,7 @@ All API responses are returned in JSON format:
 
 ### 5. Modify frpc Instance
 
-**Endpoint:** `/frpcAct/instanceMgr/{instanceName}/modify/{field}`  
+**Endpoint:** `/frpcAct/instanceMgr/modify/{field}`  
 **Method:** POST  
 **Content-Type:** application/json  
 **Auth Required:** Yes (token)
@@ -244,6 +245,7 @@ You can modify multiple fields at once:
 **Request:**
 ```json
 {
+  "instanceName": "my_frpc",
   "token": "your_token",
   "timeStamp": 1704067200000,
   "name": "new_name",