dsh-mcp-skill-panel: DSH MCP and Skill Management Panel

The DeepSeek Harness (DSH) developer plugin `dsh-mcp-skill-panel` provides visual management of MCP servers and the skill catalog. It supports adding, editing, and testing connections to MCP servers, as well as searching, filtering, and previewing skills. The plugin modifies `cordis.patch.yml` directly; changes take effect immediately if live reload is enabled in the host. Installation requires running the specified command and restarting `dsh web`. Note that MCP settings are not shared between Web and Desktop modes, and skill management is view-only.