add app control server for launcher-to-app attachment

- Launcher detects a running app via control socket and attaches without spawning a new process
- Own-lifecycle app launches now pass --background --managed-playback; borrowed apps skip --background
- Separate plain subtitle websocket (tokens: []) from annotation websocket
- Default pauseVideoOnHover to true; update docs and config.example.jsonc
- Setup: remove plugin readiness card, add Open SubMiner Settings button

src/core/services/cli-command.ts

@@ -115,6 +115,7 @@ export interface CliCommandServiceDeps {
 interface MpvClientLike {
   setSocketPath: (socketPath: string) => void;
   connect: () => void;
+  reconnect?: () => void;
 }
 
 interface TexthookerServiceLike {
@@ -235,6 +236,10 @@ export function createCliCommandDepsRuntime(
     connectMpvClient: () => {
       const client = options.mpv.getClient();
       if (!client) return;
+      if (client.reconnect) {
+        client.reconnect();
+        return;
+      }
       client.connect();
     },
     isTexthookerRunning: () => options.texthooker.service.isRunning(),