audit week 1: creator ID tracking, channel-queue migration, deprecation cleanup

QUAL-006  store ticket.creatorId on creation; legacy split-pop returned the
          message ID for discord-msg-* tickets, breaking transcript DM, close
          log, and channel rename for context-menu-created tickets. Adds the
          field to the Ticket schema and writes a one-shot backfill script
          (scripts/backfill-creatorId.js, dry-run by default).

QUEUE-001 add enqueueOverwrite + enqueueTopic to services/channelQueue.js
          (chain on renameChains alongside enqueueMove). Migrate handleAdd /
          handleRemove / handleMove / handleTopic so permissionOverwrites,
          setParent, and setTopic no longer race pending renames or sends.
          handleMove now uses the existing enqueueMove. Initial overwrites in
          handleTicketModal stay inline; channel doesn't exist yet so no race.

DISCORD-001 replace ephemeral: true with flags: MessageFlags.Ephemeral across
            broccolini-discord.js, handlers/sharedHelpers.js, handlers/buttons.js,
            handlers/commands.js. runDeferred opts now take { flags } directly.

SEC-003   /gmailpoll min interval is 30s. Drop the 5s/10s slash-command
          choices and clamp Math.max(30000, ms) in handleGmailPoll for
          defense in depth.

QUAL-001  upgrade silent .catch(() => {}) on the lastActivity updateOne in
          handlers/messages.js to log via logError, so transient Mongo errors
          surface in the debug channel instead of disappearing.

QUAL-002  drop await from logError/logWarn calls in services/staffThread.js
          and services/pinMessage.js — fire-and-forget per CLAUDE.md hard rule.

QUAL-003  wrap stray setTimeouts (handleConfirmCloseRequest force-close timer,
          runFinalClose channel-delete + overflow-cleanup, checkAutoClose
          delete-after-email) in trackTimeout via lazy require so they clear
          on shutdown.

broccolini-discord.js

@@ -2,7 +2,7 @@
  * Entry point – initializes the Discord bot, wires event handlers,
  * connects to MongoDB, starts Gmail polling, and runs the Express healthcheck.
  */
-const { Client, GatewayIntentBits, Partials } = require('discord.js');
+const { Client, GatewayIntentBits, Partials, MessageFlags } = require('discord.js');
 const express = require('express');
 const { connectMongoDB, closeMongoDB } = require('./db-connection');
 const { CONFIG } = require('./config');
@@ -86,7 +86,7 @@ const client = new Client({
 
 // --- EVENT: interactionCreate ---
 async function safeReplyError(interaction) {
-  const payload = { content: 'Something went wrong.', ephemeral: true };
+  const payload = { content: 'Something went wrong.', flags: MessageFlags.Ephemeral };
   if (interaction.deferred || interaction.replied) {
     await interaction.followUp(payload).catch(() => {});
   } else {
@@ -132,13 +132,13 @@ client.on('interactionCreate', async interaction => {
       
       await interaction.reply({ 
         content: 'Signature settings saved successfully!', 
-        ephemeral: true 
+        flags: MessageFlags.Ephemeral 
       });
     } catch (err) {
       console.error('Signature modal submit error:', err);
       await interaction.reply({ 
         content: 'Failed to save signature settings.', 
-        ephemeral: true 
+        flags: MessageFlags.Ephemeral 
       });
     }
     return;