chore(env): add NEXT_TELEMETRY_DISABLED example env

Author: yoshinorin

.env.example

@@ -1,15 +1,18 @@
+# Next.js Configuration
+NEXT_TELEMETRY_DISABLED=1
+
 # OpenTelemetry Configuration
 
-# Individual endpoint configuration (preferred)
+## Individual endpoint configuration (preferred)
 OTEL_EXPORTER_OTLP_TRACES_ENDPOINT=http://localhost:4318/v1/traces
 OTEL_EXPORTER_OTLP_METRICS_ENDPOINT=http://localhost:4318/v1/metrics
 OTEL_EXPORTER_OTLP_LOGS_ENDPOINT=http://localhost:4318/v1/logs
 
-# Authentication headers
-# Examples:
-# OTEL_EXPORTER_OTLP_HEADERS=Authorization=Basic {base64-encoded-credentials}
-# OTEL_EXPORTER_OTLP_HEADERS=x-api-key={your-api-key}
+## Authentication headers
+## Examples:
+## OTEL_EXPORTER_OTLP_HEADERS=Authorization=Basic {base64-encoded-credentials}
+## OTEL_EXPORTER_OTLP_HEADERS=x-api-key={your-api-key}
 OTEL_EXPORTER_OTLP_HEADERS=
 
-# Service name
+## Service name
 OTEL_SERVICE_NAME=quintet