feat: rewrite as moderation bot (#11)

## Summary

- Replaces the old AI companion bot with a full Discord moderation system
- Adds 8 slash commands: `warn`, `mute`, `unmute`, `kick`, `softban`, `ban`, `unban`, `prune`
- Adds logging for member join/leave, activity (messages, threads, voice), and moderation actions
- Audit log integration captures manual bans, kicks, timeouts, and unbans
- All applicable actions post sanctions to the Hikari sanction API
- All commands are ephemeral, use Components v2, and enforce permission + role hierarchy checks

## Test plan

- [ ] Run `pnpm register` to register all 8 commands to the guild
- [ ] Verify each command appears in Discord and is only visible to members with the appropriate permissions
- [ ] Test each command against a valid target and confirm mod log entry, DM notification, and sanction record
- [ ] Test each command against an invalid target (equal/higher role, self, bot) and confirm correct error response
- [ ] Perform a manual ban, kick, and timeout in the Discord UI and confirm audit log handler picks them up
- [ ] Perform a manual unban and confirm it logs correctly without creating a sanction
- [ ] Verify join/leave messages appear in the welcome log channel
- [ ] Verify message edits, deletes, thread events, and voice state changes appear in the activity log channel

✨ This issue was created with help from Hikari~ 🌸

Reviewed-on: #11
Co-authored-by: Hikari <hikari@nhcarrigan.com>
Co-committed-by: Hikari <hikari@nhcarrigan.com>

src/register.ts

@@ -0,0 +1,57 @@
+/**
+ * @copyright nhcarrigan
+ * @license Naomi's Public License
+ * @author Naomi Carrigan
+ */
+/* eslint-disable no-console -- Standalone registration script; no logger available */
+
+import { REST, Routes } from "discord.js";
+import { banCommand } from "./commands/ban.js";
+import { kickCommand } from "./commands/kick.js";
+import { muteCommand } from "./commands/mute.js";
+import { pruneCommand } from "./commands/prune.js";
+import { softbanCommand } from "./commands/softban.js";
+import { unbanCommand } from "./commands/unban.js";
+import { unmuteCommand } from "./commands/unmute.js";
+import { warnCommand } from "./commands/warn.js";
+import { guildConfig } from "./config/guild.js";
+
+const commandData = [
+  banCommand.data.toJSON(),
+  unbanCommand.data.toJSON(),
+  kickCommand.data.toJSON(),
+  muteCommand.data.toJSON(),
+  pruneCommand.data.toJSON(),
+  softbanCommand.data.toJSON(),
+  unmuteCommand.data.toJSON(),
+  warnCommand.data.toJSON(),
+];
+
+const rest = new REST().setToken(process.env.DISCORD_TOKEN ?? "");
+
+/* eslint-disable-next-line @typescript-eslint/consistent-type-assertions -- REST returns unknown; shape is documented by Discord API */
+const me = await rest.get(Routes.user()) as { id: string; username: string };
+console.log(`Authenticated as: ${me.username} (${me.id})`);
+
+try {
+  console.log(
+    `Registering ${commandData.length.toString()} commands for guild ${guildConfig.guildId}...`,
+  );
+
+  await rest.put(
+    Routes.applicationGuildCommands(
+      guildConfig.clientId,
+      guildConfig.guildId,
+    ),
+    { body: commandData },
+  );
+
+  console.log("Commands registered successfully.");
+} catch (error) {
+  console.error(
+    "Failed to register commands:",
+    error instanceof Error
+      ? error.message
+      : String(error),
+  );
+}