[AAE-4966] Extensible app config (#6914)

* merge app config from the extensions

* improved service injection in unit tests

* extra unit test

* fix content tests

* update code as per review

* fix lint

* fix lint

* update code and tests

* update schema

lib/extensions/src/lib/config/extension.config.ts

@@ -27,9 +27,9 @@ export interface ExtensionRef {
     $license: string;
     $runtime?: string;
     $description?: string;
-
     $dependencies?: Array<string>;
 
+    appConfig?: any;
     rules?: Array<RuleRef>;
     routes?: Array<RouteRef>;
     actions?: Array<ActionRef>;

lib/extensions/src/lib/config/schema/plugin-extension.schema.json

@@ -602,6 +602,10 @@
       "minItems": 0,
       "uniqueItems": true
     },
+    "appConfig": {
+      "description": "Application configuration parameters to add/override",
+      "type": "object"
+    },
     "rules": {
       "description": "List of rule definitions",
       "type": "array",

lib/extensions/src/lib/services/extension.service.ts

@@ -25,6 +25,7 @@ import * as core from '../evaluators/core.evaluators';
 import { ComponentRegisterService } from './component-register.service';
 import { RuleService } from './rule.service';
 import { ExtensionElement } from '../config/extension-element';
+import { BehaviorSubject } from 'rxjs';
 
 export function extensionJsonsFactory() {
     return [];
@@ -58,6 +59,9 @@ export class ExtensionService {
     features: Array<any> = [];
     authGuards: { [key: string]: Type<{}> } = {};
 
+    protected onSetup$ = new BehaviorSubject<ExtensionConfig>(this.config);
+    setup$ = this.onSetup$.asObservable();
+
     constructor(
         protected loader: ExtensionLoaderService,
         protected componentRegister: ComponentRegisterService,
@@ -103,6 +107,7 @@ export class ExtensionService {
         this.features = this.loader.getFeatures(config);
 
         this.ruleService.setup(config);
+        this.onSetup$.next(config);
     }
 
     /**