* feat(devenv): add otel-collector support for local development
- Add .devenv/docker/otel-collector/ with compose.yaml and config
- Add devenv-otel-collector and devenv-up targets to Makefile
- Update development.md with otel-collector setup instructions
- Add README.md with usage documentation for otel-collector setup
This enables developers to run the complete SigNoz stack locally,
including the OpenTelemetry Collector for receiving telemetry data
on ports 4317 (gRPC) and 4318 (HTTP).
* docs: improve collector setup wordings
* chore: fixed comment and service name
* chore: docker service name updated otel-collector -> signoz-otel-collector
