feat: publish integrations/tracevault-mcp to npm

[hashedone]

Goal

Publish the ask_tracevault MCP server (integrations/tracevault-mcp/) to npm so users can install it globally without cloning the repo:

npm install -g @<scope>/mcp-server
tracevault-mcp  # or add to .mcp.json

Open questions

• Package scope/name (TBD — depends on rename to Visdom Trace and npm org ownership)
• Whether to publish the pre-built dist/ or require users to npm run build (currently dist is gitignored)
• CI automation: publish on release-plz tag, or manual

Current workaround

npm install --prefix integrations/tracevault-mcp after cloning the repo (documented in README).