RFC 5785 defines /.well-known/ as the prefix for "well-known locations"
in URIs. This prefix is used for example by Certbot/Let's Encrypt to
request SSL certificates. PartDB doesn't need to care about this
directory, but also should not see its existence as the git tree being
"dirty".
- Add BulkSearchResponseDTO, FieldMappingDTO for type safety
- Use composition instead of inheritance in BulkSearchResultDTO
- Remove unnecessary BulkSearchRequestDTO
- Fix N+1 queries and API error handling
- Fix Add Mapping button functionality