feat(anime): add anime browser powered by Aniyomi extensions

- Add `subminer anime` / `--anime` and a tray entry to open a browser that searches installed Aniyomi extension sources, shows cover art and episodes, and plays into mpv with overlay/mining attached
- Add an Extensions tab to add repos and install/update/remove sources, and per-source settings for sources needing config
- Support searching all sources at once with streaming, per-source results and status
- Prefer Japanese audio/subtitle tracks from the source and keep the primary subtitle slot reserved for Japanese
- Fix window/tray/Dock handling so the browser and mpv can be switched between without quitting the app or losing the Dock icon
- Add anime.repos, anime.extensionsDir, anime.preferredQuality config keys (no bundled repos or discovery)

src/anime-bridge/sidecar-process.ts

@@ -0,0 +1,104 @@
+import { spawn, type ChildProcess } from 'node:child_process';
+import path from 'node:path';
+import { createServer } from 'node:net';
+import { AnimeBridgeClient } from './bridge-client';
+import type { BundleBinaries } from './sidecar-bundle';
+
+/** Cold start includes JVM boot plus AndroidCompat init; be generous. */
+export const DEFAULT_READY_TIMEOUT_MS = 30_000;
+const READY_POLL_INTERVAL_MS = 500;
+
+/** Ask the OS for a free loopback port, then hand it to the JVM. */
+export async function allocatePort(): Promise<number> {
+  return new Promise((resolve, reject) => {
+    const server = createServer();
+    server.once('error', reject);
+    server.listen(0, '127.0.0.1', () => {
+      const address = server.address();
+      if (address === null || typeof address === 'string') {
+        server.close();
+        reject(new Error('Could not allocate a loopback port for the anime bridge.'));
+        return;
+      }
+      const { port } = address;
+      server.close(() => resolve(port));
+    });
+  });
+}
+
+export interface SidecarHandle {
+  baseUrl: string;
+  port: number;
+  client: AnimeBridgeClient;
+  stop: () => Promise<void>;
+}
+
+export interface StartSidecarOptions {
+  binaries: BundleBinaries;
+  port?: number;
+  readyTimeoutMs?: number;
+  spawnImpl?: typeof spawn;
+  onLog?: (line: string) => void;
+}
+
+/**
+ * Launch the bridge and wait until it reports the capabilities this client
+ * needs. The desktop launch contract is `java -jar MExtensionServer.jar <port>`,
+ * run from the JAR's own directory.
+ */
+export async function startSidecar(options: StartSidecarOptions): Promise<SidecarHandle> {
+  const { binaries } = options;
+  const port = options.port ?? (await allocatePort());
+  const baseUrl = `http://127.0.0.1:${port}`;
+  const spawnProcess = options.spawnImpl ?? spawn;
+
+  const child: ChildProcess = spawnProcess(
+    binaries.javaPath,
+    ['-jar', binaries.jarPath, String(port)],
+    {
+      cwd: path.dirname(binaries.jarPath),
+      stdio: ['ignore', 'pipe', 'pipe'],
+    },
+  );
+
+  const log = options.onLog;
+  if (log) {
+    child.stdout?.on('data', (chunk: Buffer) => log(chunk.toString().trimEnd()));
+    child.stderr?.on('data', (chunk: Buffer) => log(chunk.toString().trimEnd()));
+  }
+
+  let exited: { code: number | null; signal: NodeJS.Signals | null } | null = null;
+  child.once('exit', (code, signal) => {
+    exited = { code, signal };
+  });
+
+  const stop = async (): Promise<void> => {
+    if (exited !== null) return;
+    // Graceful first: the server exposes a shutdown endpoint.
+    try {
+      await fetch(`${baseUrl}/stop`, { signal: AbortSignal.timeout(2000) });
+    } catch {
+      // Falling through to a signal is fine; the endpoint may already be gone.
+    }
+    if (exited === null) child.kill();
+  };
+
+  const client = new AnimeBridgeClient({ baseUrl });
+  const deadline = Date.now() + (options.readyTimeoutMs ?? DEFAULT_READY_TIMEOUT_MS);
+
+  while (Date.now() < deadline) {
+    if (exited !== null) {
+      const { code, signal } = exited as { code: number | null; signal: NodeJS.Signals | null };
+      throw new Error(
+        `Anime bridge exited before becoming ready (code ${code}, signal ${signal}).`,
+      );
+    }
+    if (await client.isReady()) return { baseUrl, port, client, stop };
+    await new Promise((resolve) => setTimeout(resolve, READY_POLL_INTERVAL_MS));
+  }
+
+  await stop();
+  throw new Error(
+    `Anime bridge did not become ready within ${options.readyTimeoutMs ?? DEFAULT_READY_TIMEOUT_MS}ms.`,
+  );
+}