feat: add regolith onboard CLI wizard with daemon installation

- Interactive setup wizard: deps check, env config, WhatsApp auth, daemon install, health check
- CLI entry point via yargs with bin registration (regolith onboard)
- Flags: --install-daemon, --non-interactive, --pairing-code, --json, --skip-*
- launchd (macOS) and systemd (Linux) service installation
- Refactored whatsapp-auth.ts to export authenticate() for programmatic use
- 72 tests across 6 test files
- Updated README.md and CLAUDE.md with onboard CLI docs

package.json

@@ -4,6 +4,9 @@
   "description": "Personal AI assistant with multi-channel support (WhatsApp, Discord) and multi-runtime backends (Claude Agent SDK, OpenCode).",
   "type": "module",
   "main": "dist/index.js",
+  "bin": {
+    "regolith": "dist/cli/index.js"
+  },
   "scripts": {
     "build": "tsc",
     "start": "node dist/index.js",
@@ -25,12 +28,14 @@
     "qrcode": "^1.5.4",
     "qrcode-terminal": "^0.12.0",
     "yaml": "^2.8.2",
+    "yargs": "^18.0.0",
     "zod": "^4.3.6"
   },
   "devDependencies": {
     "@types/better-sqlite3": "^7.6.12",
     "@types/node": "^22.10.0",
     "@types/qrcode-terminal": "^0.12.2",
+    "@types/yargs": "^17.0.35",
     "@vitest/coverage-v8": "^4.0.18",
     "fast-check": "^4.5.3",
     "prettier": "^3.8.1",