feat: schedule filters overhaul, local fonts, configurable statuses/levels

Schedule filters:
- Airbnb-style filter modal with sections: directions, trainer, status, level, days, time
- Multi-select trainer filter with search input
- Custom time range (from-to) with preset shortcuts
- Gold tag design for class types, statuses, and levels
- Hover tooltips on level/status options with descriptions from config
- Filter icon button inline with view toggle (По дням / По группам)

Admin schedule:
- Configurable experience levels and statuses (add/edit/reorder/delete)
- New scheduleConfig DB section with auto-save
- Status/level dropdowns in class editor read from config
- Status select built dynamically from config
- New status field on ScheduleClass for custom statuses

Other:
- Local fonts (Inter + Oswald) bundled in public/fonts — no Google Fonts dependency
- SelectField combobox: search in main input field, no separate search inside dropdown
- Fix carousel trainer label flash on drag release

src/data/content.ts

@@ -449,6 +449,16 @@ export const siteContent: SiteContent = {
       },
     ],
   },
+  scheduleConfig: {
+    levels: [
+      { value: "Начинающий/Без опыта", description: "Для тех, кто только начинает заниматься" },
+      { value: "Продвинутый", description: "Для учеников с опытом от 6 месяцев" },
+    ],
+    statuses: [
+      { key: "hasSlots", label: "Есть места", description: "В группе есть свободные места" },
+      { key: "recruiting", label: "Набор открыт", description: "Идёт набор в новую группу" },
+    ],
+  },
   news: {
     title: "Новости",
     items: [],