feat: build out discord support agent (#4)

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- [x] I have read and agree to the [Code of Conduct](https://docs.nhcarrigan.com/community/coc/)
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- [x] I have pinned the dependencies to a specific patch version.

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### Tests

- [ ] My contribution adds new code, and I have added tests to cover it.
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Reviewed-on: #4
Co-authored-by: Naomi Carrigan <commits@nhcarrigan.com>
Co-committed-by: Naomi Carrigan <commits@nhcarrigan.com>

bot/prod/utils/checkEntitlement.js

@@ -0,0 +1,41 @@
+/**
+ * @copyright nhcarrigan
+ * @license Naomi's Public License
+ * @author Naomi Carrigan
+ */
+import { entitledGuilds, entitledUsers } from "../config/entitlements.js";
+/**
+ * Checks if a user has subscribed.
+ * @param hikari - Hikari's Discord instance.
+ * @param user - The user to check.
+ * @returns A boolean indicating whether the user has an active subscription.
+ */
+const checkUserEntitlement = async (hikari, user) => {
+    if (entitledUsers.includes(user.id)) {
+        return true;
+    }
+    const entitlements = await hikari.application?.entitlements.fetch({
+        excludeDeleted: true,
+        excludeEnded: true,
+        user: user,
+    });
+    return Boolean(entitlements && entitlements.size > 0);
+};
+/**
+ * Checks if a guild has subscribed.
+ * @param hikari - Hikari's Discord instance.
+ * @param guild - The guild to check.
+ * @returns A boolean indicating whether the guild has an active subscription.
+ */
+const checkGuildEntitlement = async (hikari, guild) => {
+    if (entitledGuilds.includes(guild.id)) {
+        return true;
+    }
+    const entitlements = await hikari.application?.entitlements.fetch({
+        excludeDeleted: true,
+        excludeEnded: true,
+        guild: guild,
+    });
+    return Boolean(entitlements && entitlements.size > 0);
+};
+export { checkUserEntitlement, checkGuildEntitlement };