app: Scaffold Android TV PeerTube client (MVP)

Start the SmartTube-inspired PeerTube TV client as a Kotlin + Compose
for TV app. It targets any PeerTube instance (v1 API), with JTube as
the default, and covers login 0, local/own video listings 1-2, search
3, subscriptions 4, server-backed history 5 and HLS/progressive
playback with watching reports 6.

Password is only used for the OAuth password grant and never stored;
tokens are kept in EncryptedSharedPreferences. Building needs JDK 17+
(see README); the Gradle wrapper is checked in so no local Gradle is
required.

build.gradle.kts

@@ -0,0 +1,6 @@
+plugins {
+    alias(libs.plugins.android.application) apply false
+    alias(libs.plugins.kotlin.android) apply false
+    alias(libs.plugins.kotlin.compose) apply false
+    alias(libs.plugins.kotlin.serialization) apply false
+}