fix: Unbreak a use case for #1110 / fix for #1121 (#1123)

"Function" is builtin, but anything prefixed or suffixed for whatever
reason shouldn't be handled the same way. So check if the final result
is in builtin list, not the original unmodified name

I have concerns about maybeSnakeToCamel being called earlier now, but i
can't find any tests for options.snakeToCamel.includes("keys") so i'm
not sure if i broke anything

```
  /** Converts `key` to TS/JS camel-case idiom, unless overridden not to. */
💡export function maybeSnakeToCamel(key: string, options: Pick<Options, "snakeToCamel">): string {
    if (options.snakeToCamel.includes("keys") && key.includes("_")) {
      return snakeToCamel(key);
    } else {
      return key;
    }
  }
```

But all tests pass

integration/test-1110/test-1110-test.ts

@@ -1,8 +1,13 @@
-import { UserRule } from "./test-1110";
+import { UserRule, Nested_Function } from "./test-1110";
 
 describe("test-1110", () => {
   it("Able to create a partial user rule with reserved word messages", () => {
     const simple: UserRule = UserRule.fromPartial({ UUID: "foo" });
     expect(simple).toBeTruthy();
   });
+
+  it("built in handling should only be done to top level", () => {
+    const nestedFunction: Nested_Function = Nested_Function.fromPartial({});
+    expect(nestedFunction).toBeTruthy();
+  });
 });

integration/test-1110/test-1110.proto

@@ -25,5 +25,12 @@ message Function {
     string name = 2;
 }
 
+message Nested {
+  message Function {
+      string namespace = 1;
+      string name = 2;
+  }
+}
+
 service APIService {
 }

src/visit.ts

@@ -39,7 +39,7 @@ export function visit(
     const protoFullName = protoPrefix + enumDesc.name;
     // I.e. FooBar_ZazInner
     const tsFullName = tsPrefix + maybeSnakeToCamel(enumDesc.name, options);
-    const tsFullNameWithAffixes = `${options.typePrefix}${tsFullName}${options.typeSuffix}`;
+    const tsFullNameWithAffixes = messageName(`${options.typePrefix}${tsFullName}${options.typeSuffix}`);
     const nestedSourceInfo = sourceInfo.open(childEnumType, index);
     enumFn(tsFullNameWithAffixes, enumDesc, nestedSourceInfo, protoFullName);
   });
@@ -51,8 +51,8 @@ export function visit(
     // I.e. Foo_Bar.Zaz_Inner
     const protoFullName = protoPrefix + message.name;
     // I.e. FooBar_ZazInner
-    const tsFullName = tsPrefix + maybeSnakeToCamel(messageName(message), options);
-    const tsFullNameWithAffixes = `${options.typePrefix}${tsFullName}${options.typeSuffix}`;
+    const tsFullName = tsPrefix + maybeSnakeToCamel(message.name, options);
+    const tsFullNameWithAffixes = messageName(`${options.typePrefix}${tsFullName}${options.typeSuffix}`);
     const nestedSourceInfo = sourceInfo.open(childType, index);
     messageFn(tsFullNameWithAffixes, message, nestedSourceInfo, protoFullName);
     const delim = options.useSnakeTypeName ? "_" : "";
@@ -63,8 +63,7 @@ export function visit(
 const builtInNames = ["Date", "Function"];
 
 /** Potentially suffixes `Message` to names to avoid conflicts, i.e. with `Date`. */
-function messageName(message: DescriptorProto): string {
-  const { name } = message;
+function messageName(name: string): string {
   return builtInNames.includes(name) ? `${name}Message` : name;
 }