feat(python): add files lance/schema.py, lance/file.py, lance/util.py for pyright typecheck (#3454)

This just adds the lance/schema.py, lance/file.py, lance/util.py files
such that they can be checked with pyright. Fixes
[#329](#3294)

Co-authored-by: Renato Marroquin <renato.marroquin@oracle.com>

Author: renato2099

python/pyproject.toml

@@ -77,6 +77,9 @@ include = [
     "python/lance/debug.py",
     "python/lance/tracing.py",
     "python/lance/dependencies.py",
+    "python/lance/schema.py",
+    "python/lance/file.py",
+    "python/lance/util.py",
 ]
 # Dependencies like pyarrow make this difficult to enforce strictly.
 reportMissingTypeStubs = "warning"