feat(core): add Electron runtime, services, and app composition

src/main/runtime/mpv-client-runtime-service.test.ts

@@ -0,0 +1,40 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { createMpvClientRuntimeServiceFactory } from './mpv-client-runtime-service';
+
+test('mpv runtime service factory constructs client, binds handlers, and connects', () => {
+  const calls: string[] = [];
+  let constructedSocketPath = '';
+
+  class FakeClient {
+    connect(): void {
+      calls.push('connect');
+    }
+    constructor(socketPath: string) {
+      constructedSocketPath = socketPath;
+      calls.push('construct');
+    }
+  }
+
+  const createRuntimeService = createMpvClientRuntimeServiceFactory({
+    createClient: FakeClient,
+    socketPath: '/tmp/mpv.sock',
+    options: {
+      getResolvedConfig: () => ({}),
+      autoStartOverlay: true,
+      setOverlayVisible: () => {},
+      shouldBindVisibleOverlayToMpvSubVisibility: () => false,
+      isVisibleOverlayVisible: () => false,
+      getReconnectTimer: () => null,
+      setReconnectTimer: () => {},
+    },
+    bindEventHandlers: () => {
+      calls.push('bind');
+    },
+  });
+
+  const client = createRuntimeService();
+  assert.ok(client instanceof FakeClient);
+  assert.equal(constructedSocketPath, '/tmp/mpv.sock');
+  assert.deepEqual(calls, ['construct', 'bind', 'connect']);
+});