[ez] ComponentDeclaration transforms only into FunctionDeclaration

ComponentDeclarations can only be transformed into FunctionDeclarations, so the 
types were wrong

compiler/forget/packages/babel-plugin-react-forget/src/Entrypoint/Program.ts

@@ -330,7 +330,7 @@ function shouldVisitNode(
   fn: NodePath<t.FunctionDeclaration | t.ArrowFunctionExpression>,
   pass: CompilerPass
 ): boolean {
-  if (pass.opts.enableOnlyOnReactScript) {
+  if (pass.opts.enableOnlyOnReactScript && fn.isFunctionDeclaration()) {
     return isComponentDeclaration(fn.node);
   }
 

compiler/forget/packages/babel-plugin-react-forget/src/Utils/ComponentDeclaration.ts

@@ -1,18 +1,17 @@
 import * as t from "@babel/types";
 
-type FunctionDeclOrExpr = t.FunctionDeclaration | t.ArrowFunctionExpression;
-type ComponentDeclaration = FunctionDeclOrExpr & {
+export type ComponentDeclaration = t.FunctionDeclaration & {
   __componentDeclaration: boolean;
 };
 
 export function isComponentDeclaration(
-  node: FunctionDeclOrExpr
+  node: t.FunctionDeclaration
 ): node is ComponentDeclaration {
   return Object.prototype.hasOwnProperty.call(node, "__componentDeclaration");
 }
 
 export function parseComponentDeclaration(
-  node: FunctionDeclOrExpr
+  node: t.FunctionDeclaration
 ): ComponentDeclaration | null {
   return isComponentDeclaration(node) ? node : null;
 }