docs: add error status codes for /token

src/controllers/token/index.ts

@@ -11,6 +11,7 @@ import { saveToken } from "~/models/token";
 import type { Env } from "~/types/env";
 import {
   ErrorResponse,
+  ErrorResponseSchema,
   SuccessResponse,
   SuccessResponseSchema,
 } from "~/types/schema";
@@ -49,6 +50,22 @@ const route = createRoute({
       },
       description: "Saved token successfully",
     },
+    412: {
+      content: {
+        "application/json": {
+          schema: ErrorResponseSchema,
+        },
+      },
+      description: "Token already exists",
+    },
+    500: {
+      content: {
+        "application/json": {
+          schema: ErrorResponseSchema,
+        },
+      },
+      description: "Unknown error occurred",
+    },
   },
 });