remover booker, that's overdosed

It also brings the problem of consolidating bookers over multiple
bookings. The amount of data is not justifying having it in an own
entity

db/booking.ts

@@ -3,13 +3,17 @@ import { v4 as uuidv4 } from 'uuid'
 import { dateFormatBackend, getDays, nowInTz } from '../helpers/date'
 
 import { Bill } from './bill'
-import { Booker } from './booker'
 import { BOOKING_STATUS, VALIDATION_ERRORS } from './enums'
 import { getBookedDays } from './index'
 
 export type Booking = {
   uuid: string
-  booker?: Booker
+  name: string
+  email: string
+  phone: string
+  street: string
+  zip: string
+  city: string
   bill?: Bill
   startDate: string
   endDate: string
@@ -36,11 +40,12 @@ const BookingSchema = new mongoose.Schema<BookingDocument>(
       default: uuidv4,
       index: true,
     },
-    booker: {
-      type: mongoose.Schema.Types.ObjectId,
-      ref: 'Booker',
-      required: true,
-    },
+    name: { type: String, required: true },
+    email: { type: String, required: true, minlength: 5 },
+    phone: { type: String, required: false },
+    street: { type: String, required: true },
+    zip: { type: String, required: true },
+    city: { type: String, required: true },
     bill: {
       type: mongoose.Schema.Types.ObjectId,
       ref: 'Bill',