feat(gateway): remove Jev (System One) analyzer, restore LLM-only text moderation

Jev (oc/jev-1.13-free via 9router /v1/systemone) added as primary text
analyzer was underperforming. Delete the whole feature:
- jevAnalyzer.ts + its unit & live-smoke tests
- Jev-first branch in textBatchProcessor, restore pure callModerationLLM path
- AI_LLM_JEV_* config vars (zod) and .env.example entries
- @typesafe-ai/sdk dependency (+ lockfile)

Behavior: text moderation is LLM-only again, exactly as before the
Jev feature; AGENTS.md invariant 'LLM is the only judge' holds.

services/discord-gateway/package.json

@@ -23,7 +23,6 @@
     "test:e2e:live": "bash scripts/run-llm-e2e.sh"
   },
   "dependencies": {
-    "@typesafe-ai/sdk": "^0.6.0",
     "axios": "^1.20.0",
     "discord.js-selfbot-v13": "^3.7.1",
     "dotenv": "^18.0.0",