feat(api): add membership plans and subscriptions endpoints

- Add membership-plans API with GET (list active plans) and POST (create plan)
- Add membership-plans/[id] API with GET (plan details with subscriber count), PUT (update), DELETE (soft delete)
- Add memberships API with GET (list with filters) and POST (create membership for client)
- Add memberships/[id] API with GET (membership details), PUT (update/renew/change plan), DELETE (cancel)
- Add memberships/[id]/renew API for renewing memberships with hour reset
- Add clients/[id]/membership API for quick membership lookup (booking discount calculation)
- Include benefit summaries and expiring membership detection in responses

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

apps/web/app/api/clients/[id]/membership/route.ts

@@ -0,0 +1,136 @@
+import { NextRequest, NextResponse } from 'next/server';
+import { getServerSession } from 'next-auth';
+import { authOptions } from '@/lib/auth';
+import { db } from '@/lib/db';
+
+interface RouteContext {
+  params: Promise<{ id: string }>;
+}
+
+// GET /api/clients/[id]/membership - Get client's current membership (if any)
+// This is a quick lookup endpoint for booking discount calculation
+export async function GET(
+  request: NextRequest,
+  context: RouteContext
+) {
+  try {
+    const session = await getServerSession(authOptions);
+
+    if (!session?.user) {
+      return NextResponse.json(
+        { error: 'Unauthorized' },
+        { status: 401 }
+      );
+    }
+
+    const { id: clientId } = await context.params;
+
+    // Verify client exists and belongs to organization
+    const client = await db.client.findFirst({
+      where: {
+        id: clientId,
+        organizationId: session.user.organizationId,
+      },
+      select: {
+        id: true,
+        firstName: true,
+        lastName: true,
+        email: true,
+      },
+    });
+
+    if (!client) {
+      return NextResponse.json(
+        { error: 'Client not found' },
+        { status: 404 }
+      );
+    }
+
+    // Get client's active membership
+    const now = new Date();
+
+    const membership = await db.membership.findFirst({
+      where: {
+        clientId,
+        status: 'ACTIVE',
+        endDate: {
+          gte: now,
+        },
+      },
+      include: {
+        plan: {
+          select: {
+            id: true,
+            name: true,
+            price: true,
+            courtHours: true,
+            discountPercent: true,
+            benefits: true,
+          },
+        },
+      },
+      orderBy: {
+        endDate: 'desc',
+      },
+    });
+
+    // No active membership
+    if (!membership) {
+      return NextResponse.json({
+        client,
+        hasMembership: false,
+        membership: null,
+        discounts: {
+          bookingDiscount: 0,
+          storeDiscount: 0,
+        },
+      });
+    }
+
+    // Calculate discounts and remaining time
+    const sevenDaysFromNow = new Date(now.getTime() + 7 * 24 * 60 * 60 * 1000);
+    const daysUntilExpiry = Math.ceil((membership.endDate.getTime() - now.getTime()) / (1000 * 60 * 60 * 24));
+
+    // Extract store discount from benefits array
+    const storeDiscountBenefit = membership.plan.benefits?.find(b => b.includes('store discount'));
+    const storeDiscount = storeDiscountBenefit
+      ? parseInt(storeDiscountBenefit.match(/(\d+)%/)?.[1] || '0', 10)
+      : 0;
+
+    const response = {
+      client,
+      hasMembership: true,
+      membership: {
+        id: membership.id,
+        planId: membership.plan.id,
+        planName: membership.plan.name,
+        startDate: membership.startDate,
+        endDate: membership.endDate,
+        status: membership.status,
+        isExpiring: membership.endDate <= sevenDaysFromNow,
+        daysUntilExpiry,
+        autoRenew: membership.autoRenew,
+      },
+      benefits: {
+        freeHours: membership.plan.courtHours || 0,
+        hoursRemaining: membership.remainingHours || 0,
+        hoursUsed: membership.plan.courtHours && membership.remainingHours !== null
+          ? membership.plan.courtHours - membership.remainingHours
+          : 0,
+        extraBenefits: membership.plan.benefits || [],
+      },
+      discounts: {
+        bookingDiscount: membership.plan.discountPercent ? Number(membership.plan.discountPercent) : 0,
+        storeDiscount,
+      },
+    };
+
+    return NextResponse.json(response);
+  } catch (error) {
+    console.error('Error fetching client membership:', error);
+    return NextResponse.json(
+      { error: 'Failed to fetch client membership' },
+      { status: 500 }
+    );
+  }
+}