Doesn't work on openclaw

### Describe the bug

This MCP server doesn't work on openclaw

### Affected version

Online version

### Steps to reproduce the behavior

```
root@myclaw:~# openclaw mcp add github --url https://api.githubcopilot.com/mcp/ --header "Authorization=Bearer github_pat_xyz" --transport sse

OpenClaw 2026.6.11 (e085fa1) — Half butler, half debugger, full crustacean.

11:35:08 [bundle-mcp] failed to start server "github" (https://api.githubcopilot.com/mcp/): Error: SSE error: Non-200 status code (405)
MCP probe failed for "github" in /root/.openclaw/openclaw.json: Error: SSE error: Non-200 status code (405)

```

### Expected vs actual behavior

### Logs

Start by reproducing the OpenClaw command against https://api.githubcopilot.com/mcp/ with the reported SSE transport and confirm the 405 response. Trace the server's handling of that request and compare it with the transport OpenClaw expects; done means the command starts the GitHub MCP server successfully without the 405 error.

Written by the indexing model from the issue text.