配置 .gitignore 以忽略 Python 缓存文件

变更内容：
- 添加标准 Python .gitignore 规则（__pycache__、*.pyc 等）
- 从 Git 仓库移除已跟踪的 Python 缓存文件
- 添加性能分析输出文件的忽略规则

移除的文件：
- scripts/__pycache__/*.pyc (6个文件)
- src/__pycache__/*.pyc (2个文件)

原因：
- Python 缓存文件是自动生成的，不应提交到版本控制
- 这些文件与 Python 版本和操作系统相关，跨环境不兼容
- 遵循 Python 项目标准实践

影响：
- 减小仓库体积
- 避免无意义的差异
- 提高代码审查质量

.gitignore

@@ -1,6 +1,139 @@
+# ============================================================================
+# Python
+# ============================================================================
+# Byte-compiled / optimized / DLL files
+__pycache__/
+*.py[cod]
+*$py.class
+
+# C extensions
+*.so
+
+# Distribution / packaging
+.Python
+build/
+develop-eggs/
+dist/
+downloads/
+eggs/
+.eggs/
+lib/
+lib64/
+parts/
+sdist/
+var/
+wheels/
+pip-wheel-metadata/
+share/python-wheels/
+*.egg-info/
+.installed.cfg
+*.egg
+MANIFEST
+
+# PyInstaller
+*.manifest
+*.spec
+
+# Installer logs
+pip-log.txt
+pip-delete-this-directory.txt
+
+# Unit test / coverage reports
+htmlcov/
+.tox/
+.nox/
+.coverage
+.coverage.*
+.cache
+nosetests.xml
+coverage.xml
+*.cover
+*.py,cover
+.hypothesis/
+.pytest_cache/
+
+# Translations
+*.mo
+*.pot
+
+# Django stuff:
+*.log
+local_settings.py
+db.sqlite3
+db.sqlite3-journal
+
+# Flask stuff:
+instance/
+.webassets-cache
+
+# Scrapy stuff:
+.scrapy
+
+# Sphinx documentation
+docs/_build/
+
+# PyBuilder
+target/
+
+# Jupyter Notebook
+.ipynb_checkpoints
+
+# IPython
+profile_default/
+ipython_config.py
+
+# pyenv
+.python-version
+
+# pipenv
+Pipfile.lock
+
+# PEP 582
+__pypackages__/
+
+# Celery stuff
+celerybeat-schedule
+celerybeat.pid
+
+# SageMath parsed files
+*.sage.py
+
+# Environments
+.env
+.venv
+env/
+venv/
+ENV/
+env.bak/
+venv.bak/
+
+# Spyder project settings
+.spyderproject
+.spyproject
+
+# Rope project settings
+.ropeproject
+
+# mkdocs documentation
+/site
+
+# mypy
+.mypy_cache/
+.dmypy.json
+dmypy.json
+
+# Pyre type checker
+.pyre/
+
+# ============================================================================
+# 项目特定
+# ============================================================================
 # 收敛三角形输出（本地生成，不推送）
 outputs/converging_triangles/charts/
 outputs/converging_triangles/all_results.csv
 outputs/converging_triangles/report.md
 outputs/converging_triangles/strong_breakout_down.csv
 outputs/converging_triangles/strong_breakout_up.csv
+
+# 性能分析输出
+outputs/performance/*.prof