move app to app/ subdir

app/src/utils/countTokens.ts

@@ -0,0 +1,17 @@
+import { type ChatCompletion } from "openai/resources/chat";
+import { GPTTokens } from "gpt-tokens";
+import { type SupportedModel } from "~/modelProviders/openai-ChatCompletion";
+
+interface GPTTokensMessageItem {
+  name?: string;
+  role: "system" | "user" | "assistant";
+  content: string;
+}
+
+export const countOpenAIChatTokens = (
+  model: SupportedModel,
+  messages: ChatCompletion.Choice.Message[],
+) => {
+  return new GPTTokens({ model, messages: messages as unknown as GPTTokensMessageItem[] })
+    .usedTokens;
+};