feat(launcher): add runtime-aware status metadata

tests/scripts/beadboard-launcher-runtime.test.ts

@@ -0,0 +1,15 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { execFile } from 'node:child_process';
+import { promisify } from 'node:util';
+import path from 'node:path';
+
+const execFileAsync = promisify(execFile);
+const launcherPath = path.resolve('install/beadboard.mjs');
+
+test('status --json reports runtime root and install mode', async () => {
+  const { stdout } = await execFileAsync(process.execPath, [launcherPath, 'status', '--json']);
+  const payload = JSON.parse(stdout);
+  assert.ok(payload.runtimeRoot);
+  assert.ok(payload.installMode);
+});