Require Replace-Create interceptor to return Id

Clarify interceptor behavior in low-code docs: update fluent-api.md and interceptors.md to state that Replace Create interceptors must return the new entity's Id (Guid) so the system can fetch and return the created entity. Added an example showing `return result.Id;` after `db.insert(...)`, and noted that Replace-Update and Replace-Delete do not need to return a value.

docs/en/low-code/fluent-api.md

@@ -217,7 +217,7 @@ public class Organization
 }
 ````
 
-> The `Name` parameter must be one of: `"Create"`, `"Update"`, or `"Delete"`. The `InterceptorType` can be `Pre`, `Post`, or `Replace`. When `Replace` is used, the default DB operation is skipped entirely and only the JavaScript handler runs. Multiple interceptors can be added to the same class (`AllowMultiple = true`).
+> The `Name` parameter must be one of: `"Create"`, `"Update"`, or `"Delete"`. The `InterceptorType` can be `Pre`, `Post`, or `Replace`. When `Replace` is used, the default DB operation is skipped entirely and only the JavaScript handler runs. **`Replace-Create` must return the new entity's Id** (e.g. `return result.Id;` after `db.insert`). Multiple interceptors can be added to the same class (`AllowMultiple = true`).
 
 See [Interceptors](interceptors.md) for the full JavaScript context API.
 
@@ -292,7 +292,7 @@ public override void ConfigureServices(ServiceConfigurationContext context)
 | `SetParent(entityName)` | Set parent entity for nesting |
 | `SetUI(action)` | Configure entity-level UI |
 | `ConfigureProperty(name, action)` | Configure a specific property |
-| `AddInterceptor(name, type, js)` | Add a JavaScript interceptor. `name`: `"Create"`, `"Update"`, or `"Delete"`. `type`: `Pre`, `Post`, or `Replace` |
+| `AddInterceptor(name, type, js)` | Add a JavaScript interceptor. `name`: `"Create"`, `"Update"`, or `"Delete"`. `type`: `Pre`, `Post`, or `Replace`. `Replace-Create` must return the new entity's Id |
 
 ### Property Configuration Methods
 

docs/en/low-code/interceptors.md

@@ -15,13 +15,13 @@ Interceptors allow you to run custom JavaScript code before, after, or instead o
 |---------|------|---------------|
 | `Create` | `Pre` | Before entity creation — validation, default values |
 | `Create` | `Post` | After entity creation — notifications, related data |
-| `Create` | `Replace` | Instead of entity creation — the default DB insert is skipped, only JavaScript runs |
+| `Create` | `Replace` | Instead of entity creation — **must return the new entity's Id** (see below) |
 | `Update` | `Pre` | Before entity update — validation, authorization |
 | `Update` | `Post` | After entity update — sync, notifications |
-| `Update` | `Replace` | Instead of entity update — the default DB update is skipped, only JavaScript runs |
+| `Update` | `Replace` | Instead of entity update — no return value needed |
 | `Delete` | `Pre` | Before entity deletion — dependency checks |
 | `Delete` | `Post` | After entity deletion — cleanup |
-| `Delete` | `Replace` | Instead of entity deletion — the default DB delete is skipped, only JavaScript runs |
+| `Delete` | `Replace` | Instead of entity deletion — no return value needed |
 
 ## Defining Interceptors with Attributes
 
@@ -177,11 +177,13 @@ When you need to completely replace the default create operation with custom log
 {
   "commandName": "Create",
   "type": "Replace",
-  "javascript": "var data = context.commandArgs.data;\ndata['Code'] = 'PRD-' + Date.now();\nawait db.insert('LowCodeDemo.Products.Product', data);\ncontext.log('Product created with custom code: ' + data['Code']);"
+  "javascript": "var data = context.commandArgs.data;\ndata['Code'] = 'PRD-' + Date.now();\nvar result = await db.insert('LowCodeDemo.Products.Product', data);\ncontext.log('Product created with custom code: ' + data['Code']);\nreturn result.Id;"
 }
 ```
 
-> When `Replace` is used, the standard database operation does not run. You are responsible for performing any necessary persistence in your JavaScript handler.
+> **Important:** `Replace-Create` interceptors **must** return the new entity's `Id` (Guid). The system uses this value to fetch and return the created entity. Use `return result.Id;` after `db.insert(...)`.
+>
+> `Replace-Update` and `Replace-Delete` interceptors do not need to return a value.
 
 ### Pre-Update: Self-Reference Check