fix: resolve browser compatibility by avoiding Node.js process access in nodeVersionCheck

- Add environment detection using isNode() check
- Skip Node.js version validation in browser environments
- Return browser-friendly defaults when not in Node.js
- Prevents "Cannot read properties of undefined (reading 'isTTY')" error
- Ensures external bundlers (Vite, Webpack) work correctly with Brainy

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/utils/nodeVersionCheck.ts

@@ -5,6 +5,8 @@
  * This prevents V8 HandleScope locking issues in worker threads.
  */
 
+import { isNode } from './environment.js'
+
 export interface VersionInfo {
   current: string
   major: number
@@ -16,6 +18,17 @@ export interface VersionInfo {
  * Check if the current Node.js version is supported
  */
 export function checkNodeVersion(): VersionInfo {
+  // In browser environment, skip version check
+  if (!isNode()) {
+    return {
+      current: 'browser',
+      major: 0,
+      isSupported: true, // Always supported in browser
+      recommendation: 'Browser environment'
+    }
+  }
+
+  // Only access process.version in Node.js environment
   const nodeVersion = process.version
   const majorVersion = parseInt(nodeVersion.split('.')[0].substring(1))
 
@@ -35,6 +48,11 @@ export function checkNodeVersion(): VersionInfo {
 export function enforceNodeVersion(): void {
   const versionInfo = checkNodeVersion()
 
+  // Skip enforcement in browser environment
+  if (!isNode()) {
+    return
+  }
+
   if (!versionInfo.isSupported) {
     const errorMessage = [
       '🚨 BRAINY COMPATIBILITY ERROR',
@@ -65,6 +83,11 @@ export function enforceNodeVersion(): void {
 export function warnNodeVersion(): boolean {
   const versionInfo = checkNodeVersion()
 
+  // Skip warning in browser environment
+  if (!isNode()) {
+    return true
+  }
+
   if (!versionInfo.isSupported) {
     console.warn([
       '⚠️  BRAINY VERSION WARNING',