feat(hackathons): Add registration management with API endpoints and dashboard page

- Create GET endpoint to fetch hackathon registrations with search, filtering, and pagination support
- Implement CSV export functionality for hackathon registrations with proper authorization checks
- Add registrations dashboard page for hackathon management
- Support filtering by registration status and payment status
- Include search capability across registration fields (name, email, phone, institution)
- Implement proper authorization checks to ensure only company members can access registrations
- Use service role client for master_registrations table to bypass RLS policies
- Add pagination support with limit and offset parameters
- Generate timestamped CSV exports with all registration details

Author: akshay0611

app/api/hackathons/[id]/registrations/export/route.ts

@@ -0,0 +1,125 @@
+import { NextRequest, NextResponse } from 'next/server';
+import { createClient } from '@/lib/supabase/server';
+
+export const runtime = 'nodejs';
+
+// GET: Export registrations as CSV
+export async function GET(
+    request: NextRequest,
+    { params }: { params: Promise<{ id: string }> }
+) {
+    try {
+        const { id } = await params;
+        const supabase = await createClient();
+
+        // Get the current user
+        const { data: { user }, error: authError } = await supabase.auth.getUser();
+
+        if (authError || !user) {
+            return NextResponse.json(
+                { error: 'Authentication required' },
+                { status: 401 }
+            );
+        }
+
+        // Get the hackathon by slug
+        const { data: hackathon, error: hackathonError } = await supabase
+            .from('hackathons')
+            .select('id, title, company_id, slug')
+            .eq('slug', id)
+            .single();
+
+        if (hackathonError || !hackathon) {
+            return NextResponse.json(
+                { error: 'Hackathon not found' },
+                { status: 404 }
+            );
+        }
+
+        // Check if user has access to this hackathon's company
+        const { data: membership } = await supabase
+            .from('company_members')
+            .select('role')
+            .eq('company_id', hackathon.company_id)
+            .eq('user_id', user.id)
+            .single();
+
+        if (!membership) {
+            return NextResponse.json(
+                { error: 'Unauthorized access' },
+                { status: 403 }
+            );
+        }
+
+        // Get all registrations for this hackathon
+        const { data: registrations, error: regError } = await supabase
+            .from('master_registrations')
+            .select('*')
+            .eq('activity_type', 'hackathon')
+            .eq('activity_id', hackathon.id.toString())
+            .order('created_at', { ascending: false });
+
+        if (regError) {
+            console.error('Error fetching registrations:', regError);
+            return NextResponse.json(
+                { error: 'Failed to fetch registrations' },
+                { status: 500 }
+            );
+        }
+
+        // Convert to CSV
+        const headers = [
+            'ID',
+            'Full Name',
+            'Email',
+            'Phone',
+            'Institution',
+            'Department',
+            'Year of Study',
+            'Experience Level',
+            'Status',
+            'Payment Status',
+            'Payment Amount',
+            'Registration Date',
+            'Created At'
+        ];
+
+        const csvRows = [headers.join(',')];
+
+        registrations?.forEach(reg => {
+            const row = [
+                reg.id,
+                `"${reg.full_name || ''}"`,
+                `"${reg.email || ''}"`,
+                `"${reg.phone || ''}"`,
+                `"${reg.institution || ''}"`,
+                `"${reg.department || ''}"`,
+                `"${reg.year_of_study || ''}"`,
+                `"${reg.experience_level || ''}"`,
+                reg.status,
+                reg.payment_status,
+                reg.payment_amount || '',
+                reg.registration_date,
+                reg.created_at
+            ];
+            csvRows.push(row.join(','));
+        });
+
+        const csv = csvRows.join('\n');
+        const filename = `${hackathon.slug}-registrations-${new Date().toISOString().split('T')[0]}.csv`;
+
+        return new NextResponse(csv, {
+            headers: {
+                'Content-Type': 'text/csv',
+                'Content-Disposition': `attachment; filename="${filename}"`
+            }
+        });
+
+    } catch (error) {
+        console.error('Error exporting registrations:', error);
+        return NextResponse.json(
+            { error: 'Internal server error' },
+            { status: 500 }
+        );
+    }
+}