server.fn() posts to POST /__wrnexus/rpc. Dev intercepts that path before
handlers.fetch and routes it to a createRpcHandler instance built from
loadWrnServerModule; createProductionServer/createProductionHandlers had no
such route, so the request fell through to the internal-caller-gated
inter-app service RPC and 404'd.
Add resolveProdServerFunctions(), a synchronous equivalent of dev's resolve
that searches the already-statically-imported ProdManifest components/pages/
layouts for __wrnexusServerFunctions + __wrnexusRpcManifest, and wire it into
createProductionHandlers with the same validateCsrf + withServerFnRequestContext
wrapping dev uses. Move those two helpers into a new rpc-shared.ts so prod.ts
can use them without a circular import through index.ts.
Add packages/dev-server/test/prod-server-fn-rpc.test.ts covering a successful
call, CSRF rejection, and clean 404s for an unknown component/function.
