Element Call SPA integration (#1283)

* Integrate Element Call into EX, being able to open its URLs and handle the call in-app.
* Add custom scheme support with format `element:call?url=...`.
* Update androix.webkit
* Silence the foreground service notification.
- Allow foreground service tap action to re-open the ongoing call.
- Unify notification small icons in different modules using a vector one.

---------

Co-authored-by: ElementBot <benoitm+elementbot@element.io>

features/call/build.gradle.kts

@@ -0,0 +1,37 @@
+/*
+ * Copyright (c) 2023 New Vector Ltd
+ *
+ * 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.
+ */
+
+plugins {
+    id("io.element.android-compose-library")
+    alias(libs.plugins.anvil)
+    alias(libs.plugins.ksp)
+}
+
+android {
+    namespace = "io.element.android.features.call"
+}
+
+dependencies {
+    implementation(projects.libraries.architecture)
+    implementation(projects.libraries.designsystem)
+    implementation(projects.libraries.network)
+    implementation(libs.androidx.webkit)
+    ksp(libs.showkase.processor)
+
+    testImplementation(libs.test.junit)
+    testImplementation(libs.test.truth)
+    testImplementation(libs.test.robolectric)
+}