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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### Tests

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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/events/interactionCreate.js

@@ -0,0 +1,29 @@
+/**
+ * @copyright nhcarrigan
+ * @license Naomi's Public License
+ * @author Naomi Carrigan
+ */
+import { about } from "../commands/about.js";
+import { dm } from "../commands/dm.js";
+const handlers = {
+    _default: async (_, interaction) => {
+        await interaction.reply({
+            content: `Unknown command: ${interaction.commandName}`,
+            ephemeral: true,
+        });
+    },
+    about: about,
+    dm: dm,
+};
+/**
+ * Processes a slash command.
+ * @param hikari - Hikari's Discord instance.
+ * @param interaction - The command interaction payload from Discord.
+ */
+const chatInputInteractionCreate = async (hikari, interaction) => {
+    const name = interaction.commandName;
+    // eslint-disable-next-line no-underscore-dangle -- We use _default as a fallback handler.
+    const handler = handlers[name] ?? handlers._default;
+    await handler(hikari, interaction);
+};
+export { chatInputInteractionCreate };