feat(gateway): Jev (System One) as primary text moderator with LLM fallback (#80)

* feat(gateway): Jev (System One) as primary text moderator with LLM fallback

Add TypeSafe Jev via @typesafe-ai/sdk v0.6.0 as the PRIMARY analyzer for
text-only moderation sub-batches; the existing LLM stays as the fallback
for anything Jev cannot decide confidently (per-message gate rejection or
API failure) and for media batches.

- jevAnalyzer.ts: TypeSafeClient wrapper, declarative state builder
  (System One models MUST get factual state, not chat-XML — chat framing
  made Jev confidently wrong on clean messages at 0.98 confidence),
  message-id-keyed question builder (5 typed questions per message),
  cross-consistency acceptance gate (noul↔status↔severity↔action↔category),
  answer→AnalysisResult mapper, fail-open outcome.
- textBatchProcessor.ts: Jev-first per sub-batch, rejected ids + API
  failures fall back to callModerationLLM; no cross-batch pollution.
- config: AI_LLM_JEV_ENABLED/API_KEY/BASE_URL/MODEL/TIMEOUT_MS/MIN_CONFIDENCE.
- .env.example: documented all 6 Jev env vars.
- tests: unit (question/state builders, gate, mapper) + live smoke
  (gated behind AI_LLM_JEV_SMOKE=1) verified 4/4 accepted vs real 9router.

* fix: auto-fix code quality [skip ci]

services/discord-gateway/package.json

@@ -27,6 +27,7 @@
     "@discordjs/opus": "^0.10.0",
     "@discordjs/voice": "file:vendor/discord-voice-fork",
     "@snazzah/davey": "^0.1.11",
+    "@typesafe-ai/sdk": "^0.6.0",
     "axios": "^1.20.0",
     "discord.js-selfbot-v13": "^3.7.1",
     "dotenv": "^18.0.0",