Support a module API surface for custom functionality (#8246)

* Early implementation of module API surface + functions for ILAG module

* Wire up dialog functions and ILAG-needed surface

* Ensure component renders for modules get overridden

* Respond to changes from module API interface

* Use a real module-api dependency

* Update for new Dialogs interface

* Add support for getConfigValue from module API

* Update the remainder of the module API interface

* Docs & cleanup

* Add some unit tests around module stuff

Needs end-to-end tests still.

* Appease early linters

* Break import cycles by not directly depending on Lifecycle

* Appease the linter

* Fix bad merge

test/modules/AppModule-test.ts

@@ -0,0 +1,36 @@
+/*
+Copyright 2022 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import { MockModule } from "./MockModule";
+import { AppModule } from "../../src/modules/AppModule";
+
+describe("AppModule", () => {
+    describe("constructor", () => {
+        it("should call the factory immediately", () => {
+            let module: MockModule;
+            const appModule = new AppModule((api) => {
+                if (module) {
+                    throw new Error("State machine error: Factory called twice");
+                }
+                module = new MockModule(api);
+                return module;
+            });
+            expect(appModule.module).toBeDefined();
+            expect(appModule.module).toBe(module);
+            expect(appModule.api).toBeDefined();
+        });
+    });
+});