perf: lazy-load ShaderGradient and fix image cache TTL

Co-authored-by: denshooter <44590296+denshooter@users.noreply.github.com>

app/api/tech-stack/route.ts

@@ -3,7 +3,8 @@ import { getTechStack } from '@/lib/directus';
 import { checkRateLimit, getClientIp } from '@/lib/auth';
 
 export const runtime = 'nodejs';
-export const dynamic = 'force-dynamic';
+
+const CACHE_TTL = 300; // 5 minutes
 
 /**
  * GET /api/tech-stack
@@ -28,26 +29,24 @@ export async function GET(request: NextRequest) {
     const techStack = await getTechStack(locale);
 
     if (techStack && techStack.length > 0) {
-      return NextResponse.json({
-        techStack,
-        source: 'directus'
-      });
+      return NextResponse.json(
+        { techStack, source: 'directus' },
+        { headers: { 'Cache-Control': `public, s-maxage=${CACHE_TTL}, stale-while-revalidate=${CACHE_TTL * 2}` } }
+      );
     }
 
     // Fallback: return empty (component will use hardcoded fallback)
-    return NextResponse.json({
-      techStack: null,
-      source: 'fallback'
-    });
+    return NextResponse.json(
+      { techStack: null, source: 'fallback' },
+      { headers: { 'Cache-Control': `public, s-maxage=${CACHE_TTL}, stale-while-revalidate=${CACHE_TTL * 2}` } }
+    );
 
   } catch (error) {
-    console.error('Error loading tech stack:', error);
+    if (process.env.NODE_ENV === 'development') {
+      console.error('Error loading tech stack:', error);
+    }
     return NextResponse.json(
-      { 
-        techStack: null, 
-        error: 'Failed to load tech stack',
-        source: 'error' 
-      },
+      { techStack: null, error: 'Failed to load tech stack', source: 'error' },
       { status: 500 }
     );
   }