feat: remove start.sh script and add appearance preferences management

- Deleted the start.sh script for container management.
- Added AGENTS.md for project guidelines and development principles.
- Introduced new SQL migration files for user appearance preferences and platform settings.
- Implemented appearance provider to manage user interface themes and preferences.
- Created branding utility to define and manage branding-related constants and types.

Co-authored-by: Copilot <copilot@github.com>

src/app/api/auth/forgot-password/route.ts

@@ -55,6 +55,20 @@ export async function POST(request: NextRequest) {
       })
       .where(eq(users.id, user.id));
 
+    if (!env.RESEND_API_KEY) {
+      console.warn(
+        "Password reset requested, but RESEND_API_KEY is not configured.",
+      );
+      return NextResponse.json(
+        {
+          success: true,
+          message:
+            "If an account with that email exists, password reset instructions have been sent.",
+        },
+        { status: 200 },
+      );
+    }
+
     // Send password reset email using Resend
     try {
       const resend = new Resend(env.RESEND_API_KEY);