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/isSameHour.js

@@ -0,0 +1,42 @@
+import { normalizeDates } from "./_lib/normalizeDates.js";
+import { startOfHour } from "./startOfHour.js";
+
+/**
+ * The {@link isSameHour} function options.
+ */
+
+/**
+ * @name isSameHour
+ * @category Hour Helpers
+ * @summary Are the given dates in the same hour (and same day)?
+ *
+ * @description
+ * Are the given dates in the same hour (and same day)?
+ *
+ * @param dateLeft - The first date to check
+ * @param dateRight - The second date to check
+ * @param options - An object with options
+ *
+ * @returns The dates are in the same hour (and same day)
+ *
+ * @example
+ * // Are 4 September 2014 06:00:00 and 4 September 06:30:00 in the same hour?
+ * const result = isSameHour(new Date(2014, 8, 4, 6, 0), new Date(2014, 8, 4, 6, 30))
+ * //=> true
+ *
+ * @example
+ * // Are 4 September 2014 06:00:00 and 5 September 06:00:00 in the same hour?
+ * const result = isSameHour(new Date(2014, 8, 4, 6, 0), new Date(2014, 8, 5, 6, 0))
+ * //=> false
+ */
+export function isSameHour(dateLeft, dateRight, options) {
+  const [dateLeft_, dateRight_] = normalizeDates(
+    options?.in,
+    dateLeft,
+    dateRight,
+  );
+  return +startOfHour(dateLeft_) === +startOfHour(dateRight_);
+}
+
+// Fallback for modularized imports:
+export default isSameHour;