Add full OTLP/gRPC receiver terminating LogsService, TraceService, and
MetricsService Export RPCs. Decoded protobuf records are normalized via
the shared Normalizer pipeline and emitted as LogEvents on the event bus.
- gRPC server via @grpc/grpc-js with protobufjs codec
- Protobuf definitions for all three OTLP collector services
- enrichRecord() merges scope/resource attributes for normalizer
- extractDataPoints() handles gauge, sum, and histogram metrics
- Integration tests with real gRPC client/server round-trip
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
