repoprompt-tool-guidance-refresh

Update RepoPrompt tool guidance based empirically on the latest MCP server and CLI. MCP docs live in `agent/skills/repoprompt-tool-guidance-refresh/rp-prompts/mcp/`; CLI docs and the pi extension live in `agent/` (functional locations outside this skill folder). Invoke after determining that a new RepoPrompt version might have changed MCP/CLI tooling.