refactor: standardize runtime guard patterns with lodash-es (#154)

* refactor(ui): replace runtime type guards with lodash-es predicates

* refactor(runtime): migrate typeof checks to lodash-es in core modules

* refactor(ipc): standardize runtime guards with lodash-es

* test(refactor): align runtime guard checks with lodash-es

* docs(agents): add lodash-es runtime guard skill summary

src/tests/e2e/app.spec.ts

@@ -6,17 +6,18 @@ const injectCloudAccountsFailureScript = `
 (() => {
   const START_ORPC_SERVER = 'start-orpc-server';
   const originalPostMessage = window.postMessage.bind(window);
+  const isStringValue = (value) => Object.prototype.toString.call(value) === '[object String]';
 
   window.postMessage = function (message, targetOrigin, transfer) {
     if (message === START_ORPC_SERVER && Array.isArray(transfer) && transfer[0]) {
       const serverPort = transfer[0];
-      if (typeof serverPort.start === 'function') {
+      if (serverPort.start instanceof Function) {
         serverPort.start();
       }
 
       serverPort.onmessage = (event) => {
         try {
-          const request = typeof event.data === 'string' ? JSON.parse(event.data) : event.data;
+          const request = isStringValue(event.data) ? JSON.parse(event.data) : event.data;
           const requestId = request && (request.i || request.id);
           const requestUrl = (request && request.p && request.p.u) || '';
 

src/tests/scripts/project-id-request-validation.ts

@@ -1,4 +1,5 @@
 import assert from 'node:assert/strict';
+import { isEmpty, isString } from 'lodash-es';
 
 import { transformClaudeRequestIn } from '../../lib/antigravity/ClaudeRequestMapper';
 import { ProxyService } from '../../server/modules/proxy/proxy.service';
@@ -34,7 +35,7 @@ class TestableProxyService extends ProxyService {
 
 function getEnv(name: string, fallback?: string): string {
   const value = process.env[name];
-  if (value && value.trim() !== '') {
+  if (isString(value) && !isEmpty(value.trim())) {
     return value;
   }
   if (fallback !== undefined) {
@@ -46,7 +47,7 @@ function getEnv(name: string, fallback?: string): string {
 function getEnvFromList(names: string[], fallback?: string): string {
   for (const name of names) {
     const value = process.env[name];
-    if (value && value.trim() !== '') {
+    if (isString(value) && !isEmpty(value.trim())) {
       return value;
     }
   }
@@ -60,7 +61,7 @@ function getLiveHeaders(apiKey?: string): Record<string, string> {
   const headers: Record<string, string> = {
     'Content-Type': 'application/json',
   };
-  if (apiKey && apiKey.trim() !== '') {
+  if (isString(apiKey) && !isEmpty(apiKey.trim())) {
     headers.Authorization = apiKey.startsWith('Bearer ') ? apiKey : `Bearer ${apiKey}`;
   }
   return headers;
@@ -271,7 +272,7 @@ async function validateRuntimeAnthropicRequestFromRealTokenManager(): Promise<vo
   const captured = capturedBody as Record<string, unknown>;
   const tokenProjectId = selectedToken?.token?.project_id;
   const normalizedTokenProjectId =
-    typeof tokenProjectId === 'string' && tokenProjectId.trim() !== ''
+    isString(tokenProjectId) && !isEmpty(tokenProjectId.trim())
       ? tokenProjectId.trim()
       : undefined;
 

src/tests/unit/google-api-timeout.test.ts

@@ -1,4 +1,5 @@
 import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest';
+import { isString } from 'lodash-es';
 
 // Mock module to test timeout behavior
 describe('GoogleAPIService Timeout', () => {
@@ -92,13 +93,13 @@ describe('GoogleAPIService OAuth clients', () => {
   });
 
   afterEach(() => {
-    if (typeof originalOauthClientsEnv === 'string') {
+    if (isString(originalOauthClientsEnv)) {
       process.env.ANTIGRAVITY_OAUTH_CLIENTS = originalOauthClientsEnv;
     } else {
       delete process.env.ANTIGRAVITY_OAUTH_CLIENTS;
     }
 
-    if (typeof originalActiveOauthClientEnv === 'string') {
+    if (isString(originalActiveOauthClientEnv)) {
       process.env.ANTIGRAVITY_OAUTH_CLIENT_KEY = originalActiveOauthClientEnv;
     } else {
       delete process.env.ANTIGRAVITY_OAUTH_CLIENT_KEY;

src/tests/unit/setup.ts

@@ -1,11 +1,12 @@
 import '@testing-library/jest-dom';
 import * as matchers from '@testing-library/jest-dom/matchers';
+import { isUndefined } from 'lodash-es';
 import { expect, vi } from 'vitest';
 
 expect.extend(matchers);
 
 // Mock window and localStorage for Node environment
-if (typeof window === 'undefined') {
+if (isUndefined((globalThis as { window?: unknown }).window)) {
   global.window = {
     matchMedia: vi.fn().mockImplementation((query) => ({
       matches: false,