Add OpenTelemetry tracing and log export via OTLP

Shared telemetry init module in compliance-core (behind `telemetry` feature)
sets up OTLP/gRPC export for traces and logs when OTEL_EXPORTER_OTLP_ENDPOINT
is set. Falls back to console-only output when unset.

Both agent and dashboard now use the shared init. Docker Compose includes
an OTel Collector service with a config template for SigNoz, Grafana
Tempo/Loki, Jaeger, etc.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

docker-compose.yml

@@ -17,6 +17,9 @@ services:
       - "3001:3001"
       - "3002:3002"
     env_file: .env
+    environment:
+      OTEL_EXPORTER_OTLP_ENDPOINT: http://otel-collector:4317
+      OTEL_SERVICE_NAME: compliance-agent
     depends_on:
       - mongo
     volumes:
@@ -29,6 +32,9 @@ services:
     ports:
       - "8080:8080"
     env_file: .env
+    environment:
+      OTEL_EXPORTER_OTLP_ENDPOINT: http://otel-collector:4317
+      OTEL_SERVICE_NAME: compliance-dashboard
     depends_on:
       - mongo
       - agent
@@ -43,6 +49,15 @@ services:
       PREBOOT_CHROME: "true"
     restart: unless-stopped
 
+  otel-collector:
+    image: otel/opentelemetry-collector-contrib:latest
+    ports:
+      - "4317:4317"
+      - "4318:4318"
+    volumes:
+      - ./otel-collector-config.yaml:/etc/otelcol-contrib/config.yaml
+    restart: unless-stopped
+
 volumes:
   mongo_data:
   repos_data: