new feature: Split python binding in seperate packages

Feature Description

The OpenDAL Python binding now releases all its services in a single package, which makes it difficult to use and extend. I propose splitting it into separate packages, similar to what I've done with opendalfs.

graph TD;
    opendalfs.OpendalFileSystem -- import --> MemoryFileSystem;
    opendalfs.OpendalFileSystem -- import --> S3FileSystem;
    opendalfs.OpendalFileSystem -- import --> FsFileSystem;
    opendalfs.OpendalFileSystem -- import --> ...FileSystem;
    MemoryFileSystem -- use --> opendalfs-core;
    S3FileSystem -- use --> opendalfs-core;
    FsFileSystem -- use --> opendalfs-core;
    ...FileSystem -- use --> opendalfs-core;
    opendalfs-core -- use -->opendal["Apache OpenDAL"];

Problem and Solution

OpenDAL Python is large yet still doesn't cover all the services users need.

We can divide it into multiple packages, making opendal a virtual meta-package that only provides the Python API and imports the correct service on demand when needed.

For example, as I showed up in opendalfs:

https://github.com/fsspec/opendalfs/blob/e19d28eb9f82e285685f91b3c80805146759b7d7/opendalfs/fs.py#L8-L25

    def __init__(self, scheme, *args, **kwargs):
        super().__init__(*args, **kwargs)

        try:
            # Load the module dynamically based on scheme
            module = importlib.import_module(f"opendalfs_service_{scheme}")
            # Get the file system class based on scheme
            fs_class = getattr(module, f"{scheme.capitalize()}FileSystem")
            # initialize the file system with the kwargs
            self.fs = fs_class(**kwargs)
        except ImportError:
            raise ImportError(
                f"Cannot import opendal_service_{scheme}, please check if the module exists"
            )
        except AttributeError:
            raise AttributeError(
                f"Cannot find {scheme.capitalize()}FileSystem in opendal_service_{scheme}"
            )

Additional Context

No response

Are you willing to contribute to the development of this feature?

[ ] Yes, I am willing to contribute to the development of this feature.

apache / opendal