Create Libraries and basic tooltip

libs/_internal/controllers/src/index.ts

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+export * from './lib/destroy.controller';

libs/_internal/controllers/src/lib/destroy.controller.ts

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+import { ReactiveController, ReactiveControllerHost } from 'lit';
+import { Subject } from 'rxjs';
+
+export class DestroyController implements ReactiveController {
+  /** Private variables */
+  private readonly _host: ReactiveControllerHost;
+  private readonly destroy$ = new Subject<void>();
+
+  /** Protected variables */
+
+  /** Public variables */
+  public readonly destroy = this.destroy$.asObservable();
+
+  /** constructor & lifecylce */
+  constructor(host: ReactiveControllerHost) {
+    (this._host = host).addController(this);
+  }
+
+  /** Public methods */
+  public hostDisconnected() {
+    this.destroy$.next();
+    this.destroy$.complete();
+  }
+
+  /** Protected methods */
+
+  /** Private methods */
+}