chore: build Node output for Git installs

[roziscoding]

Summary

• keep Deno imports isolated in src/deps.deno.ts and Node imports in the matching src/deps.node.ts
• route source and example imports through the Deno dependency boundary so deno2node swaps the file during the Node build
• install grammy from npm for the Node-specific dependency module
• run the deno2node build from the prepare lifecycle hook so GitHub installs produce out

Verification

• npm run build succeeds
• emitted output contains out/deps.node.js and no out/deps.deno.js
• emitted out/deps.node.js imports from npm package grammy
• deno fmt --check passes
• deno lint passes
• from an empty directory with pnpm 9.15.9, installed github:grammyjs/format#chore/deno2node-git-install
• verified the installed package contains JS and declarations for core, components, and JSX runtime entrypoints
• imported grammy-rich-messages/core, grammy-rich-messages/components, grammy-rich-messages/jsx/jsx-runtime, and grammy-rich-messages/jsx/jsx-dev-runtime from the consumer workdir and executed them successfully

Notes

• pnpm 10+ requires the consumer to authorize Git dependency build scripts through its build policy (onlyBuiltDependencies / pnpm approve-builds).
• Deno test/check still fail because the existing denopkg grammY URLs return module resolution errors (TS2307); the same failure is present on the base branch and unrelated to the Node dependency split.