docs: connect fn (#58)

docs/src/content/docs/utilities/connect.md

@@ -3,6 +3,50 @@ title: connect
 description: ngxtension/connect
 ---
 
-WIP
+`connect` is a utility function that connects a signal to an observable and returns a subscription. The subscription is automatically unsubscribed when the component is destroyed. If it's not called in an injection context, it must be called with an injector or DestroyRef.
 
-Link to [connect](https://github.com/nartc/ngxtension-platform/blob/main/libs/ngxtension/connect/src/connect.ts) source code.
+```ts
+import { connect } from '@ngxtension/connect';
+```
+
+## Usage
+
+It can be helpful when you want to have a writable signal, but you want to set its value based on an observable.
+
+For example, you might want to have a signal that represents the current page number, but you want to set its value based on an observable that represents the current page number from a data service.
+
+```ts
+@Component()
+export class AppComponent implements OnDestroy {
+	private dataService = inject(DataService);
+
+	pageNumber = signal(1);
+
+	constructor() {
+		connect(this.pageNumber, this.dataService.pageNumber$);
+	}
+}
+```
+
+You can also use it not in an injection context, but you must provide an injector or DestroyRef.
+
+```ts
+@Component()
+export class AppComponent implements OnDestroy {
+	private dataService = inject(DataService);
+
+	private injector = inject(Injector);
+	// or
+	private destroyRef = inject(DestroyRef);
+
+	pageNumber = signal(1);
+
+	ngOninit() {
+		connect(this.pageNumber, this.dataService.pageNumber$, this.injector);
+
+		// or
+
+		connect(this.pageNumber, this.dataService.pageNumber$, this.destroyRef);
+	}
+}
+```