Add __all__ to __init__.py for type checker re-export compatibility

[riccardoratta]

Summary

Pyright/Pylance (and other PEP 484-compliant type checkers) do not treat from .module import Name in a package __init__.py as a public re-export. As a result, users of hdf5plugin with strict type checking enabled see errors such as:

"Blosc2" is not exported from module "hdf5plugin"

even though the import works correctly at runtime.

Root Cause

Pyright follows the rule defined in the typing spec: a name imported in a package's __init__.py is only considered a public re-export if it is:

• re-imported using the from x import y as y form, or
• listed in __all__.

The existing # noqa comments suppress linter warnings (e.g. flake8 F401) but have no effect on type checker re-export analysis.

Change

Update all public re-exports in __init__.py to use the explicit from ._filters import Blosc2 as Blosc2 form, which satisfies both type checkers and linters without requiring an __all__ declaration.

It has no runtime behaviour changes.

[t20100]

Thanks for the contribution!

[t20100]

from_filter_options is missing:

Suggested change

	"PLUGIN_PATH",
	"PLUGIN_PATH",
	"from_filter_options",

[t20100]

I propose to remove the *_ID constants from __all__: The ids are accessible from the filter classes, e.g., Blosc2.filter_id, and I would consider deprecating the *_ID constants (not in this PR).

Suggested change

	# Filter ID constants
	"BLOSC_ID",
	"BLOSC2_ID",
	"BSHUF_ID",
	"BZIP2_ID",
	"FCIDECOMP_ID",
	"LZ4_ID",
	"SPERR_ID",
	"SZ_ID",
	"SZ3_ID",
	"ZFP_ID",
	"ZSTD_ID",

[riccardoratta]

Done, I've added from_filter_options and removed the IDs.