feat: early check-in / late checkout fees with room-level configuration

- DB migration 016: add early_checkin_fee, late_checkout_fee to rooms table
- Backend rooms: support new fee columns in POST/PATCH
- Backend hotel-settings GET: also returns check_in_time, check_out_time
- Room type + RoomPayload: add earlyCheckinFee, lateCheckoutFee fields
- RoomModal: add fee amount inputs in pricing section
- SettingsPage: add toggles for early_checkin_enabled / late_checkout_enabled
- BookingDetailPanel: on check-in shows fee warning + adds payment record if
  current time is before checkInTime and fee is set on the room; same logic
  for check-out after checkOutTime

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/lib/api.ts

@@ -381,6 +381,7 @@ export interface RoomPayload {
   sortOrder?: number; allowHourly?: boolean; hourlyRate?: number
   extraPlace?: unknown; childPolicy?: unknown
   description?: string; photos?: string[]
+  earlyCheckinFee?: number | null; lateCheckoutFee?: number | null
 }
 
 function toRoomPayload(r: Partial<RoomPayload>): Record<string, unknown> {
@@ -402,8 +403,10 @@ function toRoomPayload(r: Partial<RoomPayload>): Record<string, unknown> {
   if (r.hourlyRate        !== undefined) out.hourly_rate        = r.hourlyRate
   if (r.extraPlace        !== undefined) out.extra_place        = r.extraPlace
   if (r.childPolicy       !== undefined) out.child_policy       = r.childPolicy
-  if (r.description       !== undefined) out.description        = r.description
-  if (r.photos            !== undefined) out.photos             = r.photos
+  if (r.description       !== undefined) out.description          = r.description
+  if (r.photos            !== undefined) out.photos               = r.photos
+  if (r.earlyCheckinFee   !== undefined) out.early_checkin_fee    = r.earlyCheckinFee
+  if (r.lateCheckoutFee   !== undefined) out.late_checkout_fee    = r.lateCheckoutFee
   return out
 }