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

* refactor(helpers): separate functions into files

* idk

* idk

src/helpers/channels/edit_channel_overwrite.ts

@@ -0,0 +1,28 @@
+import { RequestManager } from "../../rest/request_manager.ts";
+import { Overwrite } from "../../types/mod.ts";
+import { endpoints } from "../../util/constants.ts";
+import {
+  calculateBits,
+  requireBotGuildPermissions,
+} from "../../util/permissions.ts";
+
+/** Edit the channel permission overwrites for a user or role in this channel. Requires `MANAGE_ROLES` permission. */
+export async function editChannelOverwrite(
+  guildID: string,
+  channelID: string,
+  overwriteID: string,
+  options: Omit<Overwrite, "id">,
+) {
+  await requireBotGuildPermissions(guildID, ["MANAGE_ROLES"]);
+
+  const result = await RequestManager.put(
+    endpoints.CHANNEL_OVERWRITE(channelID, overwriteID),
+    {
+      allow: calculateBits(options.allow),
+      deny: calculateBits(options.deny),
+      type: options.type,
+    },
+  );
+
+  return result;
+}