fix: Set Content-Type header to text/plain for Discord login request

src/components/repo/authv2.ts

@@ -55,6 +55,9 @@ export class AuthV2Repo {
             await this.request("/auth/discord", {
                 method: "POST",
                 body: token,
+                headers: {
+                    "Content-Type": "text/plain",
+                },
             })
                 .then((value) => value.json())
                 .then((value) => ResponseUserSchema.parse(value));