Fix 3-month availability by raising Beds24 chunk limit and balancing chunks.

The /inventory/rooms/offers endpoint allows up to 99 nights, but the
chunking threshold was set to 90. This caused 90-99 night stays to be
split unnecessarily, often leaving a 1- or 2-night final chunk that fell
below the room's minimum stay and produced a false "unavailable" result.

Now the limit is 99 and chunks are split into equal-sized pieces, so
stays around 3 months (and longer) avoid tiny trailing chunks.

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

src/lib/beds24.ts

@@ -184,7 +184,7 @@ async function fetchOffer(
 // is long-term stays (1–12+ months), we work around it by splitting longer
 // stays into consecutive chunks of at most this many nights each, querying
 // each separately, and summing the results.
-const MAX_NIGHTS_PER_OFFER_REQUEST = 90;
+const MAX_NIGHTS_PER_OFFER_REQUEST = 99;
 
 export async function getAvailability(
   params: Beds24AvailabilityParams
@@ -242,13 +242,20 @@ async function getAvailabilityInChunks(
   params: Beds24AvailabilityParams,
   totalNights: number
 ): Promise<Beds24AvailabilityResponse> {
+  // Split into as few chunks as possible, each ≤ 99 nights, and keep the
+  // chunk sizes as equal as possible. This avoids tiny final chunks that
+  // would fall below a room's minimum-stay rule and return no offer.
+  const numChunks = Math.ceil(totalNights / MAX_NIGHTS_PER_OFFER_REQUEST);
+  let baseChunkSize = Math.floor(totalNights / numChunks);
+  let remainder = totalNights % numChunks;
+
   let cursor = params.start;
-  let remaining = totalNights;
   let totalPrice = 0;
   let currency = "EUR";
 
-  while (remaining > 0) {
-    const chunkNights = Math.min(remaining, MAX_NIGHTS_PER_OFFER_REQUEST);
+  for (let i = 0; i < numChunks; i++) {
+    const chunkNights = baseChunkSize + (remainder > 0 ? 1 : 0);
+    remainder--;
     const chunkEnd = addDaysToDateString(cursor, chunkNights);
 
     const offer = await fetchOffer(
@@ -273,7 +280,6 @@ async function getAvailabilityInChunks(
     totalPrice += offer.price;
     currency = offer.currency;
     cursor = chunkEnd;
-    remaining -= chunkNights;
   }
 
   return {