Element Call ringing notifications (#2978)

- Add `ActiveCallManager` to handle incoming and ongoing calls.
- Add ringing call notifications with full screen intents and missed call ones as part of the 'conversation' notifications.

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

features/call/api/build.gradle.kts

@@ -0,0 +1,31 @@
+/*
+ * Copyright (c) 2024 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-library")
+    id("kotlin-parcelize")
+}
+
+android {
+    namespace = "io.element.android.features.call.api"
+}
+
+dependencies {
+    implementation(projects.anvilannotations)
+    implementation(projects.libraries.architecture)
+    implementation(projects.libraries.core)
+    implementation(projects.libraries.matrix.api)
+}

features/call/api/src/main/kotlin/io/element/android/features/call/api/CallType.kt

@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 2024 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.
+ */
+
+package io.element.android.features.call.api
+
+import android.os.Parcelable
+import io.element.android.libraries.architecture.NodeInputs
+import io.element.android.libraries.matrix.api.core.RoomId
+import io.element.android.libraries.matrix.api.core.SessionId
+import kotlinx.parcelize.Parcelize
+
+sealed interface CallType : NodeInputs, Parcelable {
+    @Parcelize
+    data class ExternalUrl(val url: String) : CallType
+
+    @Parcelize
+    data class RoomCall(
+        val sessionId: SessionId,
+        val roomId: RoomId,
+    ) : CallType
+}

features/call/api/src/main/kotlin/io/element/android/features/call/api/ElementCallEntryPoint.kt

@@ -0,0 +1,53 @@
+/*
+ * Copyright (c) 2024 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.
+ */
+
+package io.element.android.features.call.api
+
+import io.element.android.libraries.matrix.api.core.EventId
+import io.element.android.libraries.matrix.api.core.UserId
+
+/**
+ * Entry point for the call feature.
+ */
+interface ElementCallEntryPoint {
+    /**
+     * Start a call of the given type.
+     * @param callType The type of call to start.
+     */
+    fun startCall(callType: CallType)
+
+    /**
+     * Handle an incoming call.
+     * @param callType The type of call.
+     * @param eventId The event id of the event that started the call.
+     * @param senderId The user id of the sender of the event that started the call.
+     * @param roomName The name of the room the call is in.
+     * @param senderName The name of the sender of the event that started the call.
+     * @param avatarUrl The avatar url of the room or DM.
+     * @param timestamp The timestamp of the event that started the call.
+     * @param notificationChannelId The id of the notification channel to use for the call notification.
+     */
+    fun handleIncomingCall(
+        callType: CallType.RoomCall,
+        eventId: EventId,
+        senderId: UserId,
+        roomName: String?,
+        senderName: String?,
+        avatarUrl: String?,
+        timestamp: Long,
+        notificationChannelId: String,
+    )
+}