Simplify and remove magic strings

packages/server/src/jsRunner.ts

@@ -107,10 +107,8 @@ export function init() {
           }
         }
 
-        // We need to warp up the actual run in a `cb` function to be able to extract its value from isolated-vm
-        js = js.replace(/run\(\);$/, "cb(run());")
         const script = jsIsolate.compileModuleSync(
-          `import helpers from "compiled_module";${js}`,
+          `import helpers from "compiled_module";const result=${js};cb(result)`,
           {}
         )
 

packages/string-templates/src/helpers/javascript.js

@@ -42,7 +42,7 @@ module.exports.processJS = (handlebars, context) => {
   try {
     // Wrap JS in a function and immediately invoke it.
     // This is required to allow the final `return` statement to be valid.
-    const js = `function run(){${atob(handlebars)}};run();`
+    const js = `(function(){${atob(handlebars)}})();`
 
     // Our $ context function gets a value from context.
     // We clone the context to avoid mutation in the binding affecting real