Refactor UI components for consistency and clarity across the application

- Updated AGENTS.md with new guidelines for UI consistency, including badge and modal styles.
- Refactored layout.tsx to improve the placement of the progressive blur effect.
- Enhanced NotFound component text for better user guidance.
- Replaced HeroFocusButton with HeroBaslik and KapanisCta in the Home component for improved clarity.
- Added SiteFooter to multiple pages for consistent footer display.
- Removed ListemSekmeleri component and adjusted ListemPage to streamline functionality.
- Updated various components to ensure consistent styling and user experience.

src/components/header-gate.tsx

@@ -2,7 +2,8 @@
 
 import { usePathname } from "next/navigation";
 
-// Header'ın gizleneceği rotalar (tam eşleşme veya alt yol)
+// Site kromunun (banner, header, üst/alt blur) gizleneceği rotalar
+// (tam eşleşme veya alt yol)
 const HIDDEN_PREFIXES = ["/giris"];
 
 export function HeaderGate({ children }: { children: React.ReactNode }) {