feat: add codex review failover and suppress output hardening

.env.example

@@ -1,6 +1,7 @@
 # ===== EJClaw Environment Configuration =====
 # Copy this file to .env and fill in the values.
 # For dual-service (Codex), also create .env.codex with DISCORD_BOT_TOKEN for the Codex bot.
+# For review failover, create .env.codex-review with a third Discord bot token.
 
 # --- Required ---
 DISCORD_BOT_TOKEN=                    # Discord bot token (Claude bot)
@@ -25,13 +26,6 @@ ASSISTANT_NAME=claude                 # Trigger name (@claude)
 GROQ_API_KEY=                         # Groq Whisper (primary, free: console.groq.com)
 # OPENAI_API_KEY also used as Whisper fallback
 
-# --- Provider fallback (optional — Claude 429 → alternative) ---
-# FALLBACK_PROVIDER_NAME=kimi
-# FALLBACK_BASE_URL=https://api.kimi.com/coding
-# FALLBACK_AUTH_TOKEN=
-# FALLBACK_MODEL=kimi-k2.5
-# FALLBACK_COOLDOWN_MS=600000
-
 # --- Usage dashboard (optional) ---
 # STATUS_CHANNEL_ID=                  # Discord channel for live status updates
 # USAGE_DASHBOARD=true                # Enable usage dashboard