feat: enhance platform dashboard UX and add security controls

- Move Add Company button to Companies card header for better context
- Add smart Save Changes button that only appears when data is modified
- Implement navigation protection with unsaved changes warnings
- Add company status checks to prevent suspended companies from processing data
- Fix platform dashboard showing incorrect user counts
- Add dark mode toggle to platform interface
- Add copy-to-clipboard for generated credentials
- Fix cookie conflicts between regular and platform auth
- Add invitedBy and invitedAt tracking fields to User model
- Improve overall platform management workflow and security

app/api/platform/companies/[id]/users/route.ts

@@ -66,7 +66,7 @@ export async function POST(
       data: {
         name,
         email,
-        hashedPassword,
+        password: hashedPassword,
         role,
         companyId,
         invitedBy: session.user.email,