refactor(helpers): separate functions into files (#667)

* refactor(helpers): separate functions into files

* idk

* idk

src/helpers/roles/remove_role.ts

@@ -0,0 +1,36 @@
+import { botID } from "../../bot.ts";
+import { RequestManager } from "../../rest/request_manager.ts";
+import { Errors } from "../../types/mod.ts";
+import { endpoints } from "../../util/constants.ts";
+import {
+  isHigherPosition,
+  requireBotGuildPermissions,
+} from "../../util/permissions.ts";
+
+/** Remove a role from the member */
+export async function removeRole(
+  guildID: string,
+  memberID: string,
+  roleID: string,
+  reason?: string,
+) {
+  const isHigherRolePosition = await isHigherPosition(
+    guildID,
+    botID,
+    roleID,
+  );
+  if (
+    !isHigherRolePosition
+  ) {
+    throw new Error(Errors.BOTS_HIGHEST_ROLE_TOO_LOW);
+  }
+
+  await requireBotGuildPermissions(guildID, ["MANAGE_ROLES"]);
+
+  const result = await RequestManager.delete(
+    endpoints.GUILD_MEMBER_ROLE(guildID, memberID, roleID),
+    { reason },
+  );
+
+  return result;
+}