writer: remove CBF and TIFF writers; only HDF5 is written

Delete CBFWriter and the TIFF write path from jfjoch_writer so the writer
only produces the NXmx HDF5 formats. Drop CBF/TIFF from the internal
FileWriterFormat enum and reject them in FileWriterSettings.

The CBF/TIFF values are kept (marked deprecated) in the file_writer_format
OpenAPI enum for back compatibility: incoming requests using them are now
rejected in OpenAPIConvert with a clear "no longer supported" error, and a
stale CBF/TIFF value on the CBOR wire decodes to unset rather than a removed
enumerator.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

frame_serialize/CBORStream2Deserializer.cpp

@@ -1073,8 +1073,6 @@ namespace {
             case FileWriterFormat::NXmxLegacy:
             case FileWriterFormat::NXmxIntegrated:
             case FileWriterFormat::NXmxVDS:
-            case FileWriterFormat::CBF:
-            case FileWriterFormat::TIFF:
             case FileWriterFormat::NoFile:
                 return tmp;
             default: