chore: flesh out pyproject classifiers (Python versions, extra topics)

Added per-version Python 3.10-3.12 classifiers and a couple of
additional topic/audience tags so the project is discoverable on PyPI
once it ships. No code change.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: he-yufeng

pyproject.toml

@@ -13,10 +13,17 @@ authors = [{ name = "Yufeng He", email = "40085740+he-yufeng@users.noreply.githu
 keywords = ["code-reader", "ai", "education", "non-programmer"]
 classifiers = [
     "Development Status :: 3 - Alpha",
+    "Environment :: Web Environment",
     "Intended Audience :: Education",
+    "Intended Audience :: End Users/Desktop",
     "License :: OSI Approved :: MIT License",
+    "Operating System :: OS Independent",
     "Programming Language :: Python :: 3",
+    "Programming Language :: Python :: 3.10",
+    "Programming Language :: Python :: 3.11",
+    "Programming Language :: Python :: 3.12",
     "Topic :: Education",
+    "Topic :: Software Development :: Documentation",
 ]
 dependencies = [
     "fastapi>=0.115.0",