Add a Farm.js framework guide

[Kinfe123]

Summary of changes

adds a "Run a Farm.js App" guide to the JS framework guides, plus its nav entry in docs.json and an entry on the JS frameworks page (all after deno, alphabetically). it follows the remix guide's shape and reuses the flyctl and launched snippets.

Farm.js is a full-stack framework (typed file routes, server actions, streaming ssr, with react, preact, solid, vue or svelte). the guide has the reader add a two-stage Dockerfile before fly launch, and explains why: the Dockerfile fly launch generates for a node app runs npm prune --omit=dev and then npm run start, and farm's start script calls the farm cli, which is a dev dependency, so the machine fails with farm: command not found. the guide's Dockerfile runs the self-contained server in .farm/.output with node instead.

Preview

no layout or component changes. the new page is js/frameworks/farmjs.mdx.

how i checked it, on a fresh app from npx @farm.js/create-app@latest (0.1.2):

• ran @flydotio/dockerfile on it and reproduced the failure: after npm prune --omit=dev, npm run start exits with farm: command not found
• the guide's approach works: .farm/.output copied out of the project with no node_modules serves pages, the docs route and client assets, and node .farm/.output/server/index.mjs listens on 3000 on all interfaces, matching the EXPOSE 3000 that fly launch reads
• i couldn't run a real docker build or fly launch from my machine, so that part is checked by running the same commands directly rather than inside an image

Related Fly.io community and GitHub links

none

Notes

docs.json still parses after the nav change.