[BE-56] Meeting room add-on resource booking (AV equipment, projectors)

[yusuftomilola]

Overview

Members booking a meeting room cannot request AV equipment (projectors, screens, video conferencing units, whiteboards) as part of the booking. Resource add-ons unlock an additional revenue stream and improve the booking experience for professional meetings.

Context

• Booking entity: backend/src/bookings/entities/booking.entity.ts
• CreateBookingProvider: backend/src/bookings/providers/create-booking.provider.ts
• PricingService: backend/src/bookings/pricing/pricing.service.ts

Tasks

• Create Resource entity: id, name (e.g. Projector), description (nullable), priceKoboPerSession (int, 0 = free), quantity (int, default 1), isAvailable (bool), applicableWorkspaceTypes (JSONB array — e.g. ["MEETING_ROOM"], null = all types), createdAt, updatedAt
• GET /resources — list available resources (authenticated)
• POST /resources — create resource (admin only)
• PATCH /resources/:id — update resource (admin only)
• DELETE /resources/:id — soft-delete resource (admin only)
• Add resourceIds (JSONB integer array) to Booking entity; add resourcesTotalKobo (int, default 0)
• Update CreateBookingProvider: accept optional resourceIds[] in booking DTO; validate each resource exists and is available; add resource costs to total
• GET /bookings/:id/resources — list resources on a specific booking
• POST /resources/check-availability — given a list of resource IDs and a date range, returns availability status for each (for frontend to display before booking)

Files to Modify / Create

• New: backend/src/resources/ (module, entity, controller, service)
• backend/src/bookings/entities/booking.entity.ts
• backend/src/bookings/providers/create-booking.provider.ts
• backend/src/bookings/dto/create-booking.dto.ts
• backend/src/app.module.ts