Add OpenAPI docs, frontend, migrations, and API updates

- OpenAPI: add missing endpoints (add-from-url, subscriptions, public availability)
- OpenAPI: CalendarSubscription schema, Subscriptions tag
- Frontend app
- Migrations: count_for_availability, subscriptions_sync, user_preferences, calendar_settings
- Config, rate limit, auth, calendar, booking, ICS, availability, user service updates

Made-with: Cursor

frontend/node_modules/date-fns/compareDesc.cjs

@@ -0,0 +1,45 @@
+"use strict";
+exports.compareDesc = compareDesc;
+var _index = require("./toDate.cjs");
+
+/**
+ * @name compareDesc
+ * @category Common Helpers
+ * @summary Compare the two dates reverse chronologically and return -1, 0 or 1.
+ *
+ * @description
+ * Compare the two dates and return -1 if the first date is after the second,
+ * 1 if the first date is before the second or 0 if dates are equal.
+ *
+ * @param dateLeft - The first date to compare
+ * @param dateRight - The second date to compare
+ *
+ * @returns The result of the comparison
+ *
+ * @example
+ * // Compare 11 February 1987 and 10 July 1989 reverse chronologically:
+ * const result = compareDesc(new Date(1987, 1, 11), new Date(1989, 6, 10))
+ * //=> 1
+ *
+ * @example
+ * // Sort the array of dates in reverse chronological order:
+ * const result = [
+ *   new Date(1995, 6, 2),
+ *   new Date(1987, 1, 11),
+ *   new Date(1989, 6, 10)
+ * ].sort(compareDesc)
+ * //=> [
+ * //   Sun Jul 02 1995 00:00:00,
+ * //   Mon Jul 10 1989 00:00:00,
+ * //   Wed Feb 11 1987 00:00:00
+ * // ]
+ */
+function compareDesc(dateLeft, dateRight) {
+  const diff = +(0, _index.toDate)(dateLeft) - +(0, _index.toDate)(dateRight);
+
+  if (diff > 0) return -1;
+  else if (diff < 0) return 1;
+
+  // Return 0 if diff is 0; return NaN if diff is NaN
+  return diff;
+}