Add Embedded C Expert agent for safety-critical embedded systems guidance

[ravikirandasari4]

Pull Request Checklist

• I have read and followed the CONTRIBUTING.md guidelines.
• I have read and followed the Guidance for submissions involving paid services.
• My contribution adds a new instruction, prompt, agent, skill, or workflow file in the correct directory.
• The file follows the required naming convention.
• The content is clearly structured and follows the example format.
• I have tested my instructions, prompt, agent, skill, or workflow with GitHub Copilot.
• I have run npm start and verified that README.md is up to date.
• I am targeting the staged branch for this pull request.

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Description

This contribution adds an Embedded C Expert agent designed to guide developers through the complexities of embedded C development with an emphasis on safety, compliance, and industry best practices. The agent combines expertise in C99 standards, MISRA C:2012/2025 rules, CERT C secure coding principles, and embedded systems reliability engineering. It provides context-aware recommendations for static analysis integration, defensive programming patterns, and MCU-specific constraints. The agent helps teams reduce safety violations, improve code quality, and streamline compliance audits in firmware and bare-metal applications.

Usage Notes:

• Optimal for projects targeting C99 with MISRA C compliance requirements
• Works with common embedded toolchains (IAR, GCC, GHS, ARMCC)
• Applicable to safety-critical domains (automotive, medical, industrial)
• Provides both strategic guidance and practical code examples
• Integrates with static analysis tools (Coverity, QAC, PC-lint)

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Type of Contribution

• New instruction file.
• New prompt file.
• New agent file.
• New plugin.
• New skill file.
• New agentic workflow.
• Update to existing instruction, prompt, agent, plugin, skill, or workflow.
• Other (please specify):

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Additional Notes

• This agent follows the awesome-copilot contribution guidelines and agent file specification
• The tool list (edit/editFiles, search/codebase, search/usages, execute/runInTerminal, read/terminalLastCommand, read/terminalSelection, read/problems, web/fetch) aligns with typical embedded development workflows
• Recommended model: claude-sonnet-4 for optimal performance on complex embedded systems analysis
• The agent design prioritizes correctness and safety compliance over performance optimization, reflecting embedded systems industry values
• All MISRA C and CERT C references are current as of 2025 standards
• The guidance balances pragmatism with safety rigor, avoiding over-engineering while maintaining code quality standards
• This agent complements existing agents but fills a dedicated niche for embedded C safety-critical development

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By submitting this pull request, I confirm that my contribution abides by the Code of Conduct and will be licensed under the MIT License.

[github-actions]

⚠️ This PR targets main, but PRs should target staged.

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Please close this PR and re-open it against the staged branch.

You can change the base branch using the Edit button at the top of this PR,
or run: gh pr edit 1803 --base staged