refactor(devtools): import rxjs operators from the rxjs entry point

Since RxJS 7.2, all operators are exported from the main `rxjs` entry
point, and RxJS recommends importing them from there. `rxjs/operators`
is only kept for backward compatibility and is expected to be removed in
a future major version.

Switch the remaining `rxjs/operators` imports in devtools to `rxjs`,
merging them into the existing `rxjs` import where there is one. Unlike
the framework packages, which still support RxJS 6 through their peer
dependency range, devtools is bundled with the repository's RxJS 7, so
this is safe.

No runtime or bundle size changes: both entry points expose the same
tree-shakable operators.

Author: MeAkib

devtools/projects/ng-devtools-backend/src/lib/client-event-subscribers.ts

@@ -7,7 +7,7 @@
  */
 
 import {ɵDebugSignalGraph as InternalDebugSignalGraph} from '@angular/core';
-import {debounceTime} from 'rxjs/operators';
+import {debounceTime} from 'rxjs';
 import {
   ComponentExplorerViewQuery,
   ComponentType,

devtools/projects/ng-devtools/src/lib/devtools-tabs/directive-explorer/directive-forest/component-data-source/index.ts

@@ -16,8 +16,7 @@ import {
   HydrationStatus,
   ChangeDetection,
 } from '../../../../../../../protocol';
-import {BehaviorSubject, merge, Observable} from 'rxjs';
-import {map} from 'rxjs/operators';
+import {BehaviorSubject, merge, Observable, map} from 'rxjs';
 
 import {diff} from '../../diffing';
 import {IndexedNode, indexForest} from '../index-forest';

devtools/projects/ng-devtools/src/lib/devtools-tabs/directive-explorer/property-resolver/property-data-source.ts

@@ -17,8 +17,7 @@ import {
   MessageBus,
   Properties,
 } from '../../../../../../protocol';
-import {BehaviorSubject, merge, Observable, Subscription} from 'rxjs';
-import {map} from 'rxjs/operators';
+import {BehaviorSubject, merge, Observable, Subscription, map} from 'rxjs';
 
 import {diff} from '../diffing';
 

devtools/projects/ng-devtools/src/lib/devtools-tabs/profiler/recording-timeline/recording-visualizer/tree-map-visualizer/tree-map-visualizer.component.ts

@@ -17,8 +17,7 @@ import {
   viewChild,
 } from '@angular/core';
 import {ProfilerFrame} from '../../../../../../../../protocol';
-import {Subject, Subscription} from 'rxjs';
-import {debounceTime} from 'rxjs/operators';
+import {Subject, Subscription, debounceTime} from 'rxjs';
 
 import {render} from 'webtreemap/build/treemap';
 import {TreeMapFormatter, TreeMapNode} from '../../record-formatter/tree-map-formatter';

devtools/projects/ng-devtools/src/lib/shared/signal-details/signal-value-tree/signal-data-source.ts

@@ -17,8 +17,7 @@ import {
   Properties,
   SignalNodePosition,
 } from '../../../../../../protocol';
-import {BehaviorSubject, merge, Observable, Subject} from 'rxjs';
-import {takeUntil} from 'rxjs/operators';
+import {BehaviorSubject, merge, Observable, Subject, takeUntil} from 'rxjs';
 import {FlatNode, Property} from '../../object-tree-explorer/object-tree-types';
 
 export const arrayifyProps = (

devtools/projects/ng-devtools/src/lib/shared/split/split.component.ts

@@ -23,8 +23,7 @@ import {
   ViewChildren,
 } from '@angular/core';
 import {outputFromObservable} from '@angular/core/rxjs-interop';
-import {Observable, Subject, Subscriber} from 'rxjs';
-import {debounceTime} from 'rxjs/operators';
+import {Observable, Subject, Subscriber, debounceTime} from 'rxjs';
 
 import {
   Direction,