fix(rivetkit): emit CJS-safe import.meta.url so CommonJS consumers can load rivetkit

[khaled-mansour-zid]

Summary

rivetkit's CJS build ships a verbatim import.meta.url, which is a load-time SyntaxError in any CommonJS consumer (e.g. importing rivetkit under ts-node / a CJS host process).

Root cause

getRequireFn() in rivetkit-typescript/packages/rivetkit/src/utils/node.ts uses createRequire(import.meta.url) (and carries a // TODO: This causes issues in tsup with the CJS require branch commented out). The package's tsup.config.ts deliberately sets shims: false — correctly, since the ESM shims pull in Node-only modules that break the browser build (rivetkit/client). But with shims off, tsup emits import.meta.url verbatim into the .cjs output, so:

dist/tsup/mod.cjs:  return _module.createRequire.call(void 0, import.meta.url);

fails to load in CommonJS.

Fix

Keep shims: false (don't regress the browser build) and instead define a CJS-safe replacement for import.meta.url only for the cjs format, via tsup's format-aware esbuildOptions(options, context):

if (context.format === "cjs") {
  options.define = {
    ...(options.define || {}),
    "import.meta.url": "require('url').pathToFileURL(__filename).href",
  };
}

ESM output is untouched (keeps native import.meta.url); only the CJS bundle gets the load-safe form. Single-file change to tsup.config.ts.

Notes

• Repro: require('rivetkit') from a CommonJS module against the current published build throws on import.meta.
• There is a companion packaging gap (some @rivetkit/* subpackages declare a require export condition but don't ship .cjs) — happy to follow up separately; this PR fixes the main rivetkit entry.
• Draft pending your CI (I can't build the full monorepo locally); the change is minimal and format-scoped.