fix(SW-2614): send language to API

We were missing the language param on some endpoints. We are still
missing it on some, but I left those without when we don't need it, e.g.
when only caring about the IDs in the response.

apps/scandic-web/server/routers/booking/input.ts

@@ -157,6 +157,7 @@ export const updateBookingInput = z.object({
       countryCode: z.string().optional(),
     })
     .optional(),
+  language: z.nativeEnum(Lang).transform((val) => langToApiLang[val]),
 })
 
 // Query