python: migrate to PEP 639 license-files (#456)

* python: migrate to PEP 639 license-files

- Change license from deprecated table form to SPDX expression string
- Remove deprecated License :: trove classifier
- Update build-wheels.mjs to set license-files with both SDK LICENSE
  and CLI-LICENSE.md for bundled wheels
- Update SPDX expression to 'MIT AND LicenseRef-Copilot-CLI' for
  bundled CLI wheels

* python: collapse two-step license replacement into one

Address review feedback: combine the SPDX expression and license-files
replacements into a single atomic operation to avoid fragile coupling.

Author: brettcannon

python/pyproject.toml

@@ -8,14 +8,14 @@ version = "0.1.0"
 description = "Python SDK for GitHub Copilot CLI"
 readme = "README.md"
 requires-python = ">=3.9"
-license = {text = "MIT"}
+license = "MIT"
+# license-files is set by scripts/build-wheels.mjs for bundled CLI wheels
 authors = [
     {name = "GitHub", email = "opensource@github.com"}
 ]
 classifiers = [
     "Development Status :: 3 - Alpha",
     "Intended Audience :: Developers",
-    "License :: OSI Approved :: MIT License",
     "Programming Language :: Python :: 3",
     "Programming Language :: Python :: 3.9",
     "Programming Language :: Python :: 3.10",

python/scripts/build-wheels.mjs

@@ -180,13 +180,13 @@ async function buildWheel(platform, pkgVersion, cliVersion, outputDir, licensePa
     // Create __init__.py
     writeFileSync(join(binDir, "__init__.py"), '"""Bundled Copilot CLI binary."""\n');
 
-    // Copy and modify pyproject.toml - replace license reference with file
+    // Copy and modify pyproject.toml for bundled CLI wheel
     let pyprojectContent = readFileSync(join(pythonDir, "pyproject.toml"), "utf-8");
 
-    // Replace the license specification with file reference
+    // Update SPDX expression and add license-files for both SDK and bundled CLI licenses
     pyprojectContent = pyprojectContent.replace(
-        'license = {text = "MIT"}',
-        'license = {file = "CLI-LICENSE.md"}'
+        'license = "MIT"',
+        'license = "MIT AND LicenseRef-Copilot-CLI"\nlicense-files = ["LICENSE", "CLI-LICENSE.md"]'
     );
 
     // Add package-data configuration
@@ -202,6 +202,9 @@ async function buildWheel(platform, pkgVersion, cliVersion, outputDir, licensePa
         cpSync(join(pythonDir, "README.md"), join(buildDir, "README.md"));
     }
 
+    // Copy SDK LICENSE
+    cpSync(join(repoRoot, "LICENSE"), join(buildDir, "LICENSE"));
+
     // Copy CLI LICENSE
     cpSync(licensePath, join(buildDir, "CLI-LICENSE.md"));