feat(stats): add launcher stats command and build integration

- Launcher stats subcommand with cleanup mode
- Stats frontend build integrated into Makefile
- CI workflow updated for stats package
- Config example updated with stats section
- mpv plugin menu entry for stats toggle

launcher/commands/stats-command.ts

@@ -0,0 +1,108 @@
+import fs from 'node:fs';
+import os from 'node:os';
+import path from 'node:path';
+import { runAppCommandAttached } from '../mpv.js';
+import { sleep } from '../util.js';
+import type { LauncherCommandContext } from './context.js';
+
+type StatsCommandResponse = {
+  ok: boolean;
+  url?: string;
+  error?: string;
+};
+
+type StatsCommandDeps = {
+  createTempDir: (prefix: string) => string;
+  joinPath: (...parts: string[]) => string;
+  runAppCommandAttached: (
+    appPath: string,
+    appArgs: string[],
+    logLevel: LauncherCommandContext['args']['logLevel'],
+    label: string,
+  ) => Promise<number>;
+  waitForStatsResponse: (responsePath: string) => Promise<StatsCommandResponse>;
+  removeDir: (targetPath: string) => void;
+};
+
+const defaultDeps: StatsCommandDeps = {
+  createTempDir: (prefix) => fs.mkdtempSync(path.join(os.tmpdir(), prefix)),
+  joinPath: (...parts) => path.join(...parts),
+  runAppCommandAttached: (appPath, appArgs, logLevel, label) =>
+    runAppCommandAttached(appPath, appArgs, logLevel, label),
+  waitForStatsResponse: async (responsePath) => {
+    const deadline = Date.now() + 8000;
+    while (Date.now() < deadline) {
+      try {
+        if (fs.existsSync(responsePath)) {
+          return JSON.parse(fs.readFileSync(responsePath, 'utf8')) as StatsCommandResponse;
+        }
+      } catch {
+        // retry until timeout
+      }
+      await sleep(100);
+    }
+    return {
+      ok: false,
+      error: 'Timed out waiting for stats dashboard startup response.',
+    };
+  },
+  removeDir: (targetPath) => {
+    fs.rmSync(targetPath, { recursive: true, force: true });
+  },
+};
+
+export async function runStatsCommand(
+  context: LauncherCommandContext,
+  deps: StatsCommandDeps = defaultDeps,
+): Promise<boolean> {
+  const { args, appPath } = context;
+  if (!args.stats || !appPath) {
+    return false;
+  }
+
+  const tempDir = deps.createTempDir('subminer-stats-');
+  const responsePath = deps.joinPath(tempDir, 'response.json');
+
+  try {
+    const forwarded = ['--stats', '--stats-response-path', responsePath];
+    if (args.statsCleanup) {
+      forwarded.push('--stats-cleanup');
+    }
+    if (args.statsCleanupVocab) {
+      forwarded.push('--stats-cleanup-vocab');
+    }
+    if (args.logLevel !== 'info') {
+      forwarded.push('--log-level', args.logLevel);
+    }
+    const attachedExitPromise = deps.runAppCommandAttached(
+      appPath,
+      forwarded,
+      args.logLevel,
+      'stats',
+    );
+    const startupResult = await Promise.race([
+      deps.waitForStatsResponse(responsePath).then((response) => ({ kind: 'response' as const, response })),
+      attachedExitPromise.then((status) => ({ kind: 'exit' as const, status })),
+    ]);
+    if (startupResult.kind === 'exit') {
+      if (startupResult.status !== 0) {
+        throw new Error(`Stats app exited before startup response (status ${startupResult.status}).`);
+      }
+      const response = await deps.waitForStatsResponse(responsePath);
+      if (!response.ok) {
+        throw new Error(response.error || 'Stats dashboard failed to start.');
+      }
+      return true;
+    }
+    if (!startupResult.response.ok) {
+      throw new Error(startupResult.response.error || 'Stats dashboard failed to start.');
+    }
+    const exitStatus = await attachedExitPromise;
+    if (exitStatus !== 0) {
+      throw new Error(`Stats app exited with status ${exitStatus}.`);
+    }
+    return true;
+  } finally {
+    deps.removeDir(tempDir);
+  }
+}