Revise copilot-instructions.md: consolidate redundant sections, extract language-specific rules
* Added comprehensive internal documentation files establishing coding standards and development workflows for C++, Web UI, CI/CD, and ESP-IDF components.
* Implemented CodeRabbit configuration to enforce repository-specific code review guidance and quality standards across pull requests.
* Documented development workflow procedures and contribution expectations to streamline the development process and improve code consistency.
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Co-authored-by: softhack007 <91616163+softhack007@users.noreply.github.com>
Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>
