Update setuptools version and modify license information in pyproject.toml

- Updated the required setuptools version from 61 to 77 to ensure compatibility with the latest features and improvements.
- Changed the license format in `pyproject.toml` to specify "Apache-2.0" directly and added a reference to the license file for clarity.

pyproject.toml

@@ -1,5 +1,5 @@
 [build-system]
-requires = ["setuptools>=61"]
+requires = ["setuptools>=77"]
 build-backend = "setuptools.build_meta"
 
 [project]
@@ -7,11 +7,11 @@ name = "oxipy"
 version = "0.1.0"
 description = "Python client for Oxidized API with TTP-based config parsing"
 readme = "README.md"
-license = { file = "LICENSE" }
+license = "Apache-2.0"
+license-files = ["LICENSE"]
 requires-python = ">=3.10"
 classifiers = [
     "Programming Language :: Python :: 3",
-    "License :: OSI Approved :: Apache Software License",
     "Operating System :: OS Independent",
 ]
 dependencies = [