fix(next-typescript-plugin): allow call expression for server actions (…

…#63748)

cc @shuding

### Why?

The typescript plugin in #63667 does not target the call expression or
assigned actions.

```ts
'use server'

function action() {
  return async function() {
    return 'foo'
  }
}

async function action2() {
  return 'foo'
}

export const callAction = action() // call expression
export const assignedAction = action2 // assigned
```

### Current

![Screenshot 2024-03-27 at 2 29
04 PM](https://github.com/vercel/next.js/assets/120007119/7b35edba-c423-402b-94e7-9725c4d3cccc)

### Fixed

![Screenshot 2024-03-27 at 2 29
41 PM](https://github.com/vercel/next.js/assets/120007119/e9b7c164-4053-4c56-a4fb-eb4722094355)

x-ref: #63667
Closes #63743

packages/next/src/server/typescript/rules/server-boundary.ts

@@ -97,7 +97,9 @@ const serverBoundary = {
           initializer &&
           (ts.isArrowFunction(initializer) ||
             ts.isFunctionDeclaration(initializer) ||
-            ts.isFunctionExpression(initializer))
+            ts.isFunctionExpression(initializer) ||
+            ts.isCallExpression(initializer) ||
+            ts.isIdentifier(initializer))
         ) {
           diagnostics.push(
             ...serverBoundary.getSemanticDiagnosticsForFunctionExport(
@@ -127,6 +129,8 @@ const serverBoundary = {
       | tsModule.FunctionDeclaration
       | tsModule.ArrowFunction
       | tsModule.FunctionExpression
+      | tsModule.CallExpression
+      | tsModule.Identifier
   ) {
     const ts = getTs()
     const typeChecker = getTypeChecker()