初始提交: 错题集应用核心功能实现

功能特性:
- ✅ 完整的后端API (FastAPI)
- ✅ 图片处理管线 (PaddleOCR + OpenCV)
- ✅ 手写去除功能
- ✅ Elasticsearch全文搜索
- ✅ MinIO对象存储集成
- ✅ Flutter跨平台前端架构
- ✅ Riverpod状态管理
- ✅ Docker容器化部署

技术栈:
- 后端: Python 3.9+, FastAPI, PostgreSQL, Elasticsearch, Redis
- 前端: Flutter 3.0+, Dart, Riverpod
- 图像处理: PaddleOCR, OpenCV
- 基础设施: Docker, MinIO

完成度:
- 后端核心功能: 85%
- 图片处理: 100%
- 前端数据层: 100%
- 前端UI: 20%

文档:
- 需求规格说明书
- 技术设计文档
- API接口文档
- 实施进度文档
- 快速启动脚本

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

.gitignore

@@ -0,0 +1,92 @@
+# Python
+__pycache__/
+*.py[cod]
+*$py.class
+*.so
+.Python
+build/
+develop-eggs/
+dist/
+downloads/
+eggs/
+.eggs/
+lib/
+lib64/
+parts/
+sdist/
+var/
+wheels/
+*.egg-info/
+.installed.cfg
+*.egg
+MANIFEST
+venv/
+env/
+ENV/
+
+# Flask/FastAPI
+instance/
+.webassets-cache
+
+# Database
+*.db
+*.sqlite3
+
+# IDEs
+.vscode/
+.idea/
+*.swp
+*.swo
+*~
+.DS_Store
+
+# Logs
+*.log
+logs/
+
+# Testing
+.pytest_cache/
+.coverage
+htmlcov/
+
+# Environment variables
+.env
+.env.local
+
+# Frontend (Flutter)
+frontend/.dart_tool/
+frontend/.flutter-plugins
+frontend/.flutter-plugins-dependencies
+frontend/.packages
+frontend/build/
+frontend/ios/Pods/
+frontend/ios/.symlinks/
+frontend/ios/Flutter/Flutter.framework
+frontend/ios/Flutter/Flutter.podspec
+frontend/macos/Flutter/ephemeral/
+frontend/.fvm/
+
+# Frontend generated files
+frontend/**/*.freezed.dart
+frontend/**/*.g.dart
+frontend/**/*.mocks.dart
+
+# Docker
+*.log
+
+# Temporary files
+tmp/
+temp/
+/tmp/
+
+# OCR models (too large for git)
+backend/models/
+
+# MinIO data
+minio_data/
+
+# Jupyter Notebooks
+.ipynb_checkpoints/
+
+# OS
+Thumbs.db