refactor(launcher): split CLI flow into command modules

Isolate process-side effects behind adapter seams and keep wrapper behavior stable while improving command-level testability.

launcher/config-path.ts

@@ -0,0 +1,11 @@
+import fs from 'node:fs';
+import os from 'node:os';
+import { resolveConfigFilePath } from '../src/config/path-resolution.js';
+
+export function resolveMainConfigPath(): string {
+  return resolveConfigFilePath({
+    xdgConfigHome: process.env.XDG_CONFIG_HOME,
+    homeDir: os.homedir(),
+    existsSync: fs.existsSync,
+  });
+}