New crossfile

[bparrishMines]

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List which issues are fixed by this PR. You must list at least one issue.

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[gemini-code-assist]

Code Review

This pull request introduces a major refactoring of the cross_file package, migrating it to a federated plugin architecture. This is a significant improvement that modernizes the plugin structure. My review focuses on the correctness of the new implementation.

I've found a couple of potential issues in the file stream reading logic for both Android and Darwin platforms that could lead to incorrect behavior or infinite loops. Please see the detailed comments.

Also, as a process note, the pull request description is currently empty and the pre-review checklist is not filled out. Please update the description to summarize the changes and their motivation, and complete the checklist as per the repository's contributing guidelines. The PR title should also be updated to follow the [package_name] convention.

[gemini-code-assist]

The current implementation of openRead has two potential issues:

1. It yields the entire response.bytes buffer, which may contain uninitialized data if the native read call doesn't fill the whole buffer. You should only yield the portion of the buffer that contains valid data, which is indicated by response.returnValue.
2. The do-while loop can result in an infinite loop if the underlying InputStream.read method returns 0, which is a valid return value indicating no bytes were read.

I suggest refactoring this loop to be more robust against these edge cases.

      while (bytesToRead > 0) {
        final int readSize = min(bytesToRead, maxByteArrayLen);
        final android.InputStreamReadBytesResponse response =
            await inputStream.readBytes(readSize);

        if (response.returnValue <= 0) {
          // End of stream or error.
          break;
        }

        yield response.bytes.sublist(0, response.returnValue);
        bytesToRead -= response.returnValue;
      }

[gemini-code-assist]

The do-while loop here could become an infinite loop if handle.readUpToCount returns an empty Uint8List. This can happen when reaching the end of the file. When an empty list is returned, bytes.length is 0, bytesToRead is not decremented, and the loop condition bytesToRead > 0 remains true.

To prevent this, you should check if the returned bytes is empty and break the loop if it is.

      do {
        final Uint8List? bytes = await handle.readUpToCount(
          min(bytesToRead, maxByteArrayLen),
        );

        if (bytes == null) {
          throw UnsupportedError(
            'Failed to read bytes from file: ${params.uri}',
          );
        }

        if (bytes.isEmpty) {
          break;
        }

        yield bytes;
        bytesToRead -= bytes.length;
      } while (bytesToRead > 0);