docs: 完善README文档结构和内容

[awanawana]

改进摘要

本次改进主要完善了README文档，使其更加完整和用户友好。

添加的内容

1. 安装说明 - 提供多种安装方式（pip、conda、源码）
2. 使用示例 - 添加基础和高阶使用示例代码
3. 贡献指南 - 说明如何为项目做贡献

为什么需要这些改进

• 完整的安装说明帮助新用户快速上手
• 代码示例展示核心功能用法
• 贡献指南鼓励社区参与

更改的文件

• README.md - 文档结构优化和内容补充

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这是一个自动化改进，旨在提高项目文档质量。

🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

This PR significantly improves the README by adding a clearer documentation structure, including installation methods, usage examples, and contribution guidance in Chinese 📘✨.

📊 Key Changes

• Added a new 安装 section with three installation paths:
  • pip installation
  • conda installation
  • source installation via git clone and editable install
• Added a 使用示例 section:
  • basic usage example with client initialization and processing
  • advanced usage example with configurable parameters
• Added a 贡献指南 section:
  • link to CONTRIBUTING.md
  • step-by-step development workflow for contributors
  • code style and quality expectations (standards, comments, tests, docs)

🎯 Purpose & Impact

• Improves onboarding for new users by making setup and first use easier 🚀.
• Provides practical examples that reduce ambiguity and speed up adoption.
• Strengthens contributor experience with clear workflow and coding expectations 🤝.
• Enhances overall project maintainability through better documentation structure.

[github-actions]

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I have read the CLA Document and I sign the CLA

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✅ (UltralyticsAssistant)[https://github.com/UltralyticsAssistant]
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[UltralyticsAssistant]

👋 Hello @awanawana, thank you for submitting a ultralytics/yolo-flutter-app 🚀 PR! This is an automated message to help with review readiness, and an Ultralytics engineer will assist you shortly 😊 Please review the checklist below:

• ✅ Define a Purpose: Clearly explain the purpose of your fix or feature in your PR description, and link to any relevant issues. Ensure your commit messages are clear, concise, and adhere to the project's conventions.
• ✅ Synchronize with Source: Confirm your PR is synchronized with the ultralytics/yolo-flutter-app main branch. If it's behind, update it by clicking the 'Update branch' button or by running git pull and git merge main locally.
• ✅ Ensure CI Checks Pass: Verify all Ultralytics Continuous Integration (CI) checks are passing. If any checks fail, please address the issues.
• ✅ Update Documentation: Update the relevant documentation for any new or modified features.
• ✅ Add Tests: If applicable, include or update tests to cover your changes, and confirm that all tests are passing.
• ✅ Sign the CLA: Please ensure you have signed our Contributor License Agreement if this is your first Ultralytics PR by writing "I have read the CLA Document and I sign the CLA" in a new message.
• ✅ Minimize Changes: Limit your changes to the minimum necessary for your bug fix or feature addition. "It is not daily increase but daily decrease, hack away the unessential. The closer to the source, the less wastage there is." — Bruce Lee
  For more guidance, please refer to our Contributing Guide. Don't hesitate to leave a comment if you have any questions. Thank you for contributing to Ultralytics! 🚀

[UltralyticsAssistant]

🔍 PR Review

_{Made with ❤️ by Ultralytics Actions}

Good intent and improved section structure, but several newly added README commands and code snippets are placeholders rather than executable project-specific instructions. These are high-impact documentation correctness issues that should be fixed before merge to avoid user onboarding failures.

💬 Posted 5 inline comments

[UltralyticsAssistant]

⚠️ HIGH: pip install package-name is a placeholder and not executable. Publishing placeholder install commands in README will cause immediate setup failures for users. Please replace with the real package name or remove this path if pip installation is not supported.

[UltralyticsAssistant]

⚠️ HIGH: conda install -c conda-forge package-name is also a placeholder package identifier. This command will fail as written. Use the actual conda package name/channel or remove conda instructions if unavailable.

[UltralyticsAssistant]

⚠️ HIGH: The source install example uses placeholder repository values (username/repo-name), so users cannot follow it successfully. This should point to the real repository URL and directory name.

[UltralyticsAssistant]

⚠️ HIGH: The usage examples (import package_name, package_name.Client(), client.process()) are generic placeholders rather than real project APIs. This is likely to mislead users and create copy-paste failures. Please replace with runnable examples that match this repository’s actual interfaces.

[UltralyticsAssistant]

💡 MEDIUM: The code-style guidance is Python-specific (PEP 8) in a Flutter app README, which can confuse contributors about expected standards. Consider aligning this with the project’s primary stack conventions (e.g., Dart/Flutter linting) or explicitly scoping language-specific rules.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

📢 Thoughts on this report? Let us know!