MCP server 'blocked by policy'

### Describe the bug

We have a custom MCP registry which is checked when local MCP servers are configured. Although the local MCP configuration is correct and works just fine within VSCode and IntelliJ plugin, an error message 'MCP server is blocked by policy' is shown.

It is unclear what causes this. The process log mentions the following:
```
2026-06-25T11:40:36.761Z [ERROR] MCP server "io.github.sooperset/mcp-atlassian" filtered: Server "io.github.sooperset/mcp-atlassian" found in registry but local configuration does not match the registered server identity
```

### Affected version

GitHub Copilot CLI 1.0.65

### Steps to reproduce the behavior

1. Configure an MCP server in the mcp-config.json in the ~/.copilot directory or just install it from within the Copilot CLI with `/mcp add`
2. The MCP server is blocked

### Expected behavior

_No response_

### Additional context

_No response_

Reproduce el bloqueo usando mcp-config.json en ~/.copilot o el punto de entrada /mcp add; después, inspecciona el registro del proceso para detectar la discrepancia de identidad del registro. Se considera terminado cuando se acepta un servidor MCP local configurado correctamente en lugar de informarlo como bloqueado por una política.

Escrito por el modelo de indexación a partir del texto del issue.