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/intervalToDuration.cjs

@@ -0,0 +1,73 @@
+"use strict";
+exports.intervalToDuration = intervalToDuration;
+var _index = require("./_lib/normalizeInterval.cjs");
+var _index2 = require("./add.cjs");
+var _index3 = require("./differenceInDays.cjs");
+var _index4 = require("./differenceInHours.cjs");
+var _index5 = require("./differenceInMinutes.cjs");
+var _index6 = require("./differenceInMonths.cjs");
+var _index7 = require("./differenceInSeconds.cjs");
+var _index8 = require("./differenceInYears.cjs");
+
+/**
+ * The {@link intervalToDuration} function options.
+ */
+
+/**
+ * @name intervalToDuration
+ * @category Common Helpers
+ * @summary Convert interval to duration
+ *
+ * @description
+ * Convert an interval object to a duration object.
+ *
+ * @param interval - The interval to convert to duration
+ * @param options - The context options
+ *
+ * @returns The duration object
+ *
+ * @example
+ * // Get the duration between January 15, 1929 and April 4, 1968.
+ * intervalToDuration({
+ *   start: new Date(1929, 0, 15, 12, 0, 0),
+ *   end: new Date(1968, 3, 4, 19, 5, 0)
+ * });
+ * //=> { years: 39, months: 2, days: 20, hours: 7, minutes: 5, seconds: 0 }
+ */
+function intervalToDuration(interval, options) {
+  const { start, end } = (0, _index.normalizeInterval)(options?.in, interval);
+  const duration = {};
+
+  const years = (0, _index8.differenceInYears)(end, start);
+  if (years) duration.years = years;
+
+  const remainingMonths = (0, _index2.add)(start, { years: duration.years });
+  const months = (0, _index6.differenceInMonths)(end, remainingMonths);
+  if (months) duration.months = months;
+
+  const remainingDays = (0, _index2.add)(remainingMonths, {
+    months: duration.months,
+  });
+  const days = (0, _index3.differenceInDays)(end, remainingDays);
+  if (days) duration.days = days;
+
+  const remainingHours = (0, _index2.add)(remainingDays, {
+    days: duration.days,
+  });
+  const hours = (0, _index4.differenceInHours)(end, remainingHours);
+  if (hours) duration.hours = hours;
+
+  const remainingMinutes = (0, _index2.add)(remainingHours, {
+    hours: duration.hours,
+  });
+  const minutes = (0, _index5.differenceInMinutes)(end, remainingMinutes);
+  if (minutes) duration.minutes = minutes;
+
+  const remainingSeconds = (0, _index2.add)(remainingMinutes, {
+    minutes: duration.minutes,
+  });
+  const seconds = (0, _index7.differenceInSeconds)(end, remainingSeconds);
+  if (seconds) duration.seconds = seconds;
+
+  return duration;
+}