fix: switch GMW AI source from omniroute to 9router

- Change AI_LLM_BASE_URL default from omniroute.imrnes.team to 9router.asepharyana.my.id
- Update AI_LLM_MODEL default from 'text' to 'claude-opus-5' (bare model name
  compatible with 9router/OpenAI-compatible router)
- Update .env.example and inline comments to reflect 9router
- discord-gateway config now matches backend (which already uses 9router)

services/discord-gateway/src/modules/ai-moderation/llmCaller.ts

@@ -83,7 +83,7 @@ export async function callModerationLLM(
             jsonResponse: { type: "json_object" },
             retries: 0,
             signal,
-            // Router (9router/omniroute) always streams SSE even when the
+            // Router (9router / formerly omniroute) always streams SSE even when the
             // request omits `stream`. In non-stream mode the OpenAI SDK waits
             // for the FULL body before parsing, so slow/long upstream streams
             // hit the 30s/60s timeout and abort mid-generation. Streaming mode