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/commands/unban.ts

@@ -0,0 +1,107 @@
+/**
+ * @copyright nhcarrigan
+ * @license Naomi's Public License
+ * @author Naomi Carrigan
+ */
+/* eslint-disable max-lines-per-function -- Command handlers have many validation and action steps */
+
+import {
+  InteractionContextType,
+  PermissionFlagsBits,
+  SlashCommandBuilder,
+} from "discord.js";
+import { logModerationAction } from "../modules/logModAction.js";
+import { errorReply, successReply } from "../utils/components.js";
+import { logger } from "../utils/logger.js";
+import type { Command } from "../interfaces/command.js";
+
+const unbanCommand: Command = {
+  data: new SlashCommandBuilder().
+    setName("unban").
+    setDescription("Lift a ban from a user.").
+    setDefaultMemberPermissions(PermissionFlagsBits.BanMembers).
+    setContexts([ InteractionContextType.Guild ]).
+    addUserOption((option) => {
+      return option.
+        setName("user").
+        setDescription("The user to unban.").
+        setRequired(true);
+    }).
+    addStringOption((option) => {
+      return option.
+        setName("reason").
+        setDescription("The reason for lifting the ban.").
+        setRequired(true).
+        setMaxLength(512);
+    }),
+
+  execute: async(interaction) => {
+    await interaction.deferReply({ ephemeral: true });
+
+    const hasPermission = interaction.memberPermissions?.has(
+      PermissionFlagsBits.BanMembers,
+    );
+    if (hasPermission !== true) {
+      await interaction.editReply(
+        errorReply(
+          "Insufficient Permissions",
+          "You do not have permission to use this command.",
+        ),
+      );
+      return;
+    }
+
+    const target = interaction.options.getUser("user", true);
+    const reason = interaction.options.getString("reason", true);
+
+    if (target.id === interaction.user.id) {
+      await interaction.editReply(
+        errorReply("Invalid Target", "You cannot unban yourself."),
+      );
+      return;
+    }
+
+    try {
+      await interaction.guild?.bans.fetch(target.id);
+    } catch {
+      await interaction.editReply(
+        errorReply("Not Banned", "That user does not have an active ban."),
+      );
+      return;
+    }
+
+    try {
+      await interaction.guild?.bans.remove(target.id, reason);
+    } catch {
+      await interaction.editReply(
+        errorReply(
+          "Action Failed",
+          "Failed to remove the ban. Check my permissions.",
+        ),
+      );
+      return;
+    }
+
+    await logModerationAction(interaction.client, {
+      action:         "Member Unbanned",
+      emoji:          "🔓",
+      moderatorTag:   interaction.user.username,
+      reason:         reason,
+      sanctionNumber: null,
+      source:         "Command",
+      targetId:       target.id,
+      targetTag:      target.username,
+    });
+
+    await interaction.editReply(
+      successReply(
+        "Member Unbanned",
+        `**User**: ${target.username} (\`${target.id}\`)\n**Reason**: ${reason}`,
+      ),
+    );
+  },
+};
+
+void logger.log("debug", "Unban command loaded.");
+
+export { unbanCommand };