feat: Implement robust error/not-found pages & UI components

- Introduce dedicated error pages for dashboard and video routes
- Add specific not-found pages for dashboard, projects, videos, and settings
- Implement global `not-found.tsx` for general unhandled routes
- Integrate root and dashboard layouts with ErrorBoundary and Suspense
- Add new UI components: Accordion, Hover Card, Menubar, Navigation Menu, Select, Tabs
- Update Navbar to utilize the new Navigation Menu component
- Enhance `button` component with a `link` variant for better styling
- Refine existing UI components (dialog, dropdown, input, etc.)
- Update Tailwind config with new colors and animation extensions

app/api/upload/audio/[filename]/route.ts

@@ -1,6 +1,7 @@
 import { NextResponse } from 'next/server';
 import { r2Client, R2_BUCKET_NAME } from '@/lib/r2';
 import { GetObjectCommand } from '@aws-sdk/client-s3';
+import { apiErrors } from '@/lib/api-response';
 
 // Only allow UUID filenames with safe extensions
 const SAFE_FILENAME = /^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}\.[a-z0-9]+$/i;
@@ -14,7 +15,7 @@ export async function GET(
 
     // Validate filename to prevent path traversal
     if (!SAFE_FILENAME.test(filename)) {
-      return NextResponse.json({ error: 'Invalid filename' }, { status: 400 });
+      return apiErrors.badRequest('Invalid filename');
     }
 
     const key = `voice/${filename}`;
@@ -27,7 +28,7 @@ export async function GET(
     );
 
     if (!response.Body) {
-      return NextResponse.json({ error: 'File not found' }, { status: 404 });
+      return apiErrors.notFound('File');
     }
 
     const contentType = response.ContentType || 'audio/webm';
@@ -47,12 +48,9 @@ export async function GET(
   } catch (error: unknown) {
     const errorName = error instanceof Error ? error.name : '';
     if (errorName === 'NoSuchKey') {
-      return NextResponse.json({ error: 'File not found' }, { status: 404 });
+      return apiErrors.notFound('File');
     }
     console.error('Error serving audio:', error);
-    return NextResponse.json(
-      { error: 'Failed to retrieve audio' },
-      { status: 500 }
-    );
+    return apiErrors.internalError('Failed to retrieve audio');
   }
 }

app/api/upload/audio/route.ts

@@ -1,9 +1,9 @@
-import { NextResponse } from 'next/server';
 import { auth } from '@/lib/auth';
 import { r2Client, R2_BUCKET_NAME } from '@/lib/r2';
 import { PutObjectCommand } from '@aws-sdk/client-s3';
 import { randomUUID } from 'crypto';
 import { rateLimit } from '@/lib/rate-limit';
+import { apiErrors, successResponse } from '@/lib/api-response';
 
 const MAX_FILE_SIZE = 10 * 1024 * 1024; // 10MB
 const ALLOWED_TYPES = ['audio/webm', 'audio/ogg', 'audio/mp4', 'audio/mpeg', 'audio/wav'];
@@ -17,30 +17,24 @@ export async function POST(request: Request) {
     // Require authentication
     const session = await auth();
     if (!session?.user?.id) {
-      return NextResponse.json({ error: 'Unauthorized' }, { status: 401 });
+      return apiErrors.unauthorized();
     }
 
     const formData = await request.formData();
     const file = formData.get('audio') as File | null;
 
     if (!file) {
-      return NextResponse.json({ error: 'No audio file provided' }, { status: 400 });
+      return apiErrors.badRequest('No audio file provided');
     }
 
     if (file.size > MAX_FILE_SIZE) {
-      return NextResponse.json(
-        { error: 'File too large. Maximum size is 10MB.' },
-        { status: 400 }
-      );
+      return apiErrors.badRequest('File too large. Maximum size is 10MB.');
     }
 
     // Check content type
     const contentType = file.type || 'audio/webm';
     if (!ALLOWED_TYPES.includes(contentType)) {
-      return NextResponse.json(
-        { error: `Unsupported audio format: ${contentType}` },
-        { status: 400 }
-      );
+      return apiErrors.badRequest(`Unsupported audio format: ${contentType}`);
     }
 
     // Generate unique filename
@@ -65,12 +59,9 @@ export async function POST(request: Request) {
     // Return the URL through our proxy endpoint
     const voiceUrl = `/api/upload/audio/${filename}`;
 
-    return NextResponse.json({ url: voiceUrl }, { status: 201 });
+    return successResponse({ url: voiceUrl }, 201);
   } catch (error) {
     console.error('Error uploading audio:', error);
-    return NextResponse.json(
-      { error: 'Failed to upload audio' },
-      { status: 500 }
-    );
+    return apiErrors.internalError('Failed to upload audio');
   }
 }