refactor(app): implement year filtering for accounts and enhance dashboard PDF generation

src/Duempelkas.App/Services/IEntryService.cs

@@ -8,6 +8,7 @@ public interface IEntryService
     Task<List<EntryDto>> GetEntriesAsync(int accountId, int? year);
     Task<List<EntryDto>> GetEntriesAsync(int accountId, bool currentYearOnly);
     Task<List<int>> GetEntryYearsAsync(int accountId);
+    Task<List<int>> GetAllEntryYearsAsync();
     Task<EntryDto> CreateEntryAsync(int accountId, EntryType type, DateTime date, string title, decimal amount);
     Task CreateTransferAsync(int sourceAccountId, int targetAccountId, DateTime date, string title, decimal amount);
     Task DeleteEntryAsync(int entryId);