docs: add DISABLE_TELEMETRY env var to .env.example

Document the new env var that disables all OpenTelemetry collection,
preventing export timeouts when the telemetry endpoint is unreachable.

Author: Arav-Menon

apps/sim/.env.example

@@ -96,6 +96,7 @@ CRON_SECRET=your_cron_secret # Use `openssl rand -hex 32` to generate. Authentic
 # LITELLM_BASE_URL=http://localhost:4000 # Base URL for your LiteLLM proxy (OpenAI-compatible)
 # LITELLM_API_KEY=                       # Optional bearer token if your LiteLLM proxy requires auth
 # OPENROUTER_API_KEY=                    # Optional self-hosted fallback for OpenAI knowledge-base embeddings
+# DISABLE_TELEMETRY=1                    # Disable all OpenTelemetry collection (traces, metrics, logs). Prevents export timeouts when the telemetry endpoint is unreachable
 # NEXT_PUBLIC_FORCE_HOSTED=true          # Dev only: treat this instance as hosted Sim (sim-auto pool, platform keys); ignored in production builds
 # FIREWORKS_API_KEY=                     # Optional Fireworks AI API key for model listing and inference
 # FIREWORKS_API_KEY_1=                   # Optional Fireworks API key for rotation (hosted deployments)