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/tailwindcss/dist/resolve-config-B4yBzhca.d.ts

@@ -0,0 +1,29 @@
+import { _ as _default } from './colors-C__qRT83.js';
+
+type NamedUtilityValue = {
+    kind: 'named';
+    /**
+     * ```
+     * bg-red-500
+     *    ^^^^^^^
+     *
+     * w-1/2
+     *   ^
+     * ```
+     */
+    value: string;
+    /**
+     * ```
+     * w-1/2
+     *   ^^^
+     * ```
+     */
+    fraction: string | null;
+};
+
+type PluginUtils = {
+    theme: (keypath: string, defaultValue?: any) => any;
+    colors: typeof _default;
+};
+
+export type { NamedUtilityValue as N, PluginUtils as P };