feat(automod): render sticker, role & user names in moderation views

QoL lanjutan dari fix60084b3: content pesan mentah masih nampilin
snowflake (<@&roleid>, <@userid>, <:emoji:id>) di log moderasi dan
prompt LLM. Sekarang dirender ke nama yang bisa dibaca:

- Gateway capture: metadata menyimpan mentionedRoles + mentionedUsers
  (id+name) dari message.mentions, disimpan ke metadata JSON
- renderDiscordMentions(): <@&id> -> @RoleName, <@id> -> @Username,
  <:name:id> -> :name:, fallback @role/@user — dipakai di
  conversationContext (konteks LLM) dan moderationBuilders
  (getAnalysisContent) sehingga LLM lihat nama role/user beneran,
  bukan placeholder generik
- Frontend renderMessageContent() (mirror gateway) dipasang di semua
  tempat nampilin content: message-card, message-detail(-view),
  search-overlay, search-panel, users/channels section, live-stream,
  mod-queue, review list; sticker-only message tetap [Sticker: name],
  pesan teks+sticker kini ikut nampilin nama sticker
- tsc --noEmit PASS di gateway & frontend; renderDiscordMentions
  diverifikasi manual (6 kasus: role/user/emoji/unknown/plain)

services/frontend/src/components/messages/message-card.tsx

@@ -6,7 +6,7 @@ import { Badge } from "@/components/ui/badge";
 import { Button } from "@/components/ui/button";
 import { Card, CardContent } from "@/components/ui/card";
 import { Progress } from "@/components/ui/progress";
-import { safeParseJsonArray, getMessageChannelLabel } from "@/lib/format";
+import { safeParseJsonArray, getMessageChannelLabel, renderMessageContent } from "@/lib/format";
 import type { MessageRecord } from "@/lib/types";
 import { cn } from "@/lib/utils";
 import { AiStatusBadge } from "./ai-status-badge";
@@ -96,7 +96,7 @@ export function MessageCard({
                   "italic text-muted-foreground line-through",
               )}
             >
-              {msg.content}
+              {renderMessageContent(msg.content, msg.metadata)}
             </p>
             {(() => {
               const u = extractFirstImage(msg.metadata);