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/parse/_lib/parsers/ISODayParser.js

@@ -0,0 +1,117 @@
+import { setISODay } from "../../../setISODay.js";
+import { Parser } from "../Parser.js";
+
+import { mapValue, parseNDigits } from "../utils.js";
+
+// ISO day of week
+export class ISODayParser extends Parser {
+  priority = 90;
+
+  parse(dateString, token, match) {
+    const valueCallback = (value) => {
+      if (value === 0) {
+        return 7;
+      }
+      return value;
+    };
+
+    switch (token) {
+      // 2
+      case "i":
+      case "ii": // 02
+        return parseNDigits(token.length, dateString);
+      // 2nd
+      case "io":
+        return match.ordinalNumber(dateString, { unit: "day" });
+      // Tue
+      case "iii":
+        return mapValue(
+          match.day(dateString, {
+            width: "abbreviated",
+            context: "formatting",
+          }) ||
+            match.day(dateString, {
+              width: "short",
+              context: "formatting",
+            }) ||
+            match.day(dateString, {
+              width: "narrow",
+              context: "formatting",
+            }),
+          valueCallback,
+        );
+      // T
+      case "iiiii":
+        return mapValue(
+          match.day(dateString, {
+            width: "narrow",
+            context: "formatting",
+          }),
+          valueCallback,
+        );
+      // Tu
+      case "iiiiii":
+        return mapValue(
+          match.day(dateString, {
+            width: "short",
+            context: "formatting",
+          }) ||
+            match.day(dateString, {
+              width: "narrow",
+              context: "formatting",
+            }),
+          valueCallback,
+        );
+      // Tuesday
+      case "iiii":
+      default:
+        return mapValue(
+          match.day(dateString, {
+            width: "wide",
+            context: "formatting",
+          }) ||
+            match.day(dateString, {
+              width: "abbreviated",
+              context: "formatting",
+            }) ||
+            match.day(dateString, {
+              width: "short",
+              context: "formatting",
+            }) ||
+            match.day(dateString, {
+              width: "narrow",
+              context: "formatting",
+            }),
+          valueCallback,
+        );
+    }
+  }
+
+  validate(_date, value) {
+    return value >= 1 && value <= 7;
+  }
+
+  set(date, _flags, value) {
+    date = setISODay(date, value);
+    date.setHours(0, 0, 0, 0);
+    return date;
+  }
+
+  incompatibleTokens = [
+    "y",
+    "Y",
+    "u",
+    "q",
+    "Q",
+    "M",
+    "L",
+    "w",
+    "d",
+    "D",
+    "E",
+    "e",
+    "c",
+    "t",
+    "T",
+  ];
+}