add models.json: machine-readable index; documents the v3.0-filename / V3.0.2-weights mismatch

checksums: add clean-named variants

docs: add clean-named fp16/fp32 variants

Add birdnet-geomodel-v3.0-fp32.onnx (clean filename; fp32 = genuine upstream full precision)

Add birdnet-geomodel-v3.0-fp16.onnx (clean filename; fp32 = genuine upstream full precision)

Add converted labels in BirdNET-Go format

Add BirdNET Geomodel V3.0.2 ONNX FP16 with labels and taxonomy

initial commit