Support zstd compression

[ben-z]

Resolves #4

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• tests/integration/compression/test.sh: Language not supported

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src/docker_unpack/utils.py:197

• Replace the debug print statement with a proper logger call.

print(f"calling taropen with {name=}, {mode=}, {zfobj=}")

Copilot reviewed 4 out of 5 changed files in this pull request and generated 1 comment.

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• tests/integration/compression/test.sh: Language not supported

Comments suppressed due to low confidence (2)

src/docker_unpack/utils.py:193

• The method zstandard.open does not exist. It should be zstandard.ZstdCompressor().stream_writer for writing.

zfobj = zstandard.open(fileobj or name, mode + "b", cctx=zstandard.ZstdCompressor(write_checksum=True, threads=-1))

src/docker_unpack/cli.py:34

• Constructing the mode using f-strings might lead to incorrect modes if input_file_proxy.getcomptype() returns an unexpected value.

with MyTarFile.open(fileobj=input_file_proxy, mode=f"r{'|' if input_file_proxy.supports_streaming() else ':'}{input_file_proxy.getcomptype()}") as tar: