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

internal/api/handlers/calendars.go

@@ -77,16 +77,19 @@ func (h *CalendarHandler) Update(w http.ResponseWriter, r *http.Request) {
 	}
 
 	var req struct {
-		Name     *string `json:"name"`
-		Color    *string `json:"color"`
-		IsPublic *bool   `json:"is_public"`
+		Name                   *string `json:"name"`
+		Color                  *string `json:"color"`
+		IsPublic               *bool   `json:"is_public"`
+		CountForAvailability   *bool   `json:"count_for_availability"`
+		DefaultReminderMinutes *int    `json:"default_reminder_minutes"`
+		SortOrder              *int    `json:"sort_order"`
 	}
 	if err := utils.DecodeJSON(r, &req); err != nil {
 		utils.WriteError(w, err)
 		return
 	}
 
-	cal, err := h.calSvc.Update(r.Context(), userID, calID, req.Name, req.Color, req.IsPublic)
+	cal, err := h.calSvc.Update(r.Context(), userID, calID, req.Name, req.Color, req.IsPublic, req.CountForAvailability, req.DefaultReminderMinutes, req.SortOrder)
 	if err != nil {
 		utils.WriteError(w, err)
 		return