Advertise Fusion MCP brand icons for Cursor and Hermes

[astraltrekkin]

Summary

• Fusion now advertises a full MCP identity on initialize: title, website URL, dark/light SVG icons, and a PNG — plus the same icons on every tool via _meta.
• Adds a Cursor plugin manifest (.cursor-plugin/plugin.json + mcp.json) that points at the Fusion mark so Customize / Marketplace can show our glyph instead of a generic placeholder.
• Spec-compliant clients (Inspector, future Cursor/Hermes) can render the Fusion mark. Cursor’s live “Exploring … MCP tools” chip is still the protocol logo until Cursor paints serverInfo.icons there.

Test plan

• npx tsx --test tests/mcp-identity.test.ts (initialize + plugin paths)
• Restart Cursor, toggle the Fusion MCP server off/on, confirm Settings / MCP list picks up the mark if the client version renders icons
• In Hermes Desktop, confirm Fusion still connects after fusion connect hermes (Hermes MCP tab uses a hardcoded brand map today; Fusion will show a monogram until Hermes adds a fusion brand)
• Ask the agent for fusion_status and confirm tools still work