fix(build): map the figma-mcp site to the figma package and folder

[yuriassuncx]

Why

The platform builds a monorepo MCP by running the root build with DECO_SITE_NAME=<site>. scripts/build-mcp.ts then uses that name both as the package filter (bun run --filter=<site> build) and as the folder whose dist it moves to the root.

Since #559 the site is figma-mcp, because figma is taken by an unrelated storefront. The MCP's package and folder are both figma, so the build would find no package and no figma-mcp/dist.

What

"figma-mcp": "figma" is added to FOLDER_OVERRIDES and PKG_NAME_OVERRIDES. It is the same mapping github-mcp → github already uses.

Verified

• bun run --filter=figma build produces figma/dist/server/main.js (2.68 MB).
• Moving that to ./dist gives the ./dist/server/main.js entrypoint from deploy.json.
• Pre-commit format and lint checks pass.

🤖 Generated with Claude Code

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Summary by cubic

Fixes the MCP build so the figma-mcp site resolves to the figma package and folder, which previously caused the build to fail since the site name didn't match the package or directory. Adds the same override mapping that github-mcp → github already uses.

^{Written for commit 0a03464. Summary will update on new commits.}