Submit Setlist to MCP directories and the official registry

[spaceshipmike]

Already slotted in marketing/launch-plan.md (Day -13/-12), tracked here because it's likely the highest ROI-per-hour item in the whole launch sequence — MCP server directories are how the exact target user discovers tools now.

• Official MCP registry (registry.modelcontextprotocol.io)
• Smithery registry
• MCP.so and other active directories (assess which are alive at submission time)
• Prepare the directory packet once (name, description from the frozen positioning, install command, config snippet, repo link) and reuse
• Verify the listed install path actually works post-publish (depends on the npm scope verification issue)