Add CoderPlan MCP server - OpenAI-compatible LLM API gateway

[onepaperbox]

Addition: CoderPlan MCP Server

Adds CoderPlan to the AI & LLM Integration category.

CoderPlan is an OpenAI-compatible LLM API gateway MCP server that allows AI tools (Claude Code, Cursor, VS Code, etc.) to access Claude, GPT-4o, Gemini, and 200+ models through a unified API.

• Repository: https://github.com/coderplan-ai/coderplan-mcp
• Website: https://coderplan.ai
• Category: AI & LLM Integration
• Entry format: Follows existing markdown bullet format with link and description

[wilsonccccc]

Thanks for the contribution. Please update the listing URL before this can be merged: https://github.com/coderplan-ai/coderplan-mcp currently returns 404. The coderplan-ai org exists, but this repository path is not publicly reachable. Under the new MCP Index flow, only the relevant docs/*.md category page needs to be updated; once the entry points to a public, reachable server page, we can re-review.

[wilsonccccc]

Thanks for the submission. I cannot merge this yet because the repository URL in the entry currently returns 404: https://github.com/coderplan-ai/coderplan-mcp. Please make the repo public or update the entry to a working public project URL.