Derive client domain types from the shared schema contracts

Add entity/response Zod schemas to @trek/shared (place, trip, assignment, day, budget, packing, reservation), each matched against the producing server service, and re-export them from client types.ts instead of the hand-written duplicates that had drifted (name/title, amount/total_price, owner_id/user_id, cover_url/cover_image, ...). Updates the call sites and test fixtures the corrected types surfaced; type-only, no runtime behaviour change.

client/src/store/vacayStore.ts

@@ -35,7 +35,7 @@ interface VacayYearsResponse {
 
 interface VacayEntriesResponse {
   entries: VacayEntry[]
-  companyHolidays: string[]
+  companyHolidays: { date: string; note?: string }[]
 }
 
 interface VacayStatsResponse {
@@ -109,7 +109,7 @@ interface VacayState {
   isFused: boolean
   years: number[]
   entries: VacayEntry[]
-  companyHolidays: string[]
+  companyHolidays: { date: string; note?: string }[]
   stats: VacayStat[]
   selectedYear: number
   selectedUserId: number | null