feat: replace Google OAuth with email/password authentication

Replace Google OAuth provider with email/password authentication to reduce
friction for MVP development and vibe coding workflows.

Changes:
- Remove Google OAuth configuration from auth.ts
- Add emailAndPassword provider with enabled: true
- Add email verification with sendOnSignUp: true
- Add password reset functionality
- Log verification and reset URLs to terminal (no email integration yet)

New auth pages (src/app/(auth)/):
- /login - Sign in page
- /register - Sign up page
- /forgot-password - Password reset request
- /reset-password - Password reset completion

New components (src/components/auth/):
- sign-up-form.tsx - Registration form
- forgot-password-form.tsx - Password reset request form
- reset-password-form.tsx - Password reset form

Updated components:
- sign-in-button.tsx - Now email/password form instead of Google button
- user-profile.tsx - Shows Sign in/Sign up buttons when logged out

Bug fixes:
- Fix React render error in profile page by wrapping router.push in useEffect

Config updates:
- Remove GOOGLE_CLIENT_ID and GOOGLE_CLIENT_SECRET from env.example
- Update CLAUDE.md documentation to reflect email/password auth
- Add requestPasswordReset, resetPassword, sendVerificationEmail to auth-client exports

All changes applied to both main project and create-agentic-app template.

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

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

create-agentic-app/template/src/app/profile/page.tsx

@@ -1,6 +1,6 @@
 "use client";
 
-import { useState } from "react";
+import { useState, useEffect } from "react";
 import { useRouter } from "next/navigation";
 import { Mail, Calendar, User, Shield, ArrowLeft, Lock, Smartphone } from "lucide-react";
 import { toast } from "sonner";
@@ -33,7 +33,13 @@ export default function ProfilePage() {
   const [securityOpen, setSecurityOpen] = useState(false);
   const [emailPrefsOpen, setEmailPrefsOpen] = useState(false);
 
-  if (isPending) {
+  useEffect(() => {
+    if (!isPending && !session) {
+      router.push("/");
+    }
+  }, [isPending, session, router]);
+
+  if (isPending || !session) {
     return (
       <div className="flex items-center justify-center min-h-screen">
         <div>Loading...</div>
@@ -41,11 +47,6 @@ export default function ProfilePage() {
     );
   }
 
-  if (!session) {
-    router.push("/");
-    return null;
-  }
-
   const user = session.user;
   const createdDate = user.createdAt
     ? new Date(user.createdAt).toLocaleDateString("en-US", {