Introducing developer mode for the Agent

The Datadog OpenTelemetry (DDOT) gateway simplifies managing and securing your OpenTelemetry pipeline by centralizing data collection and applying policies. It allows you to control data flow, enforce security rules (like masking PII), and optimize costs before data reaches Datadog, improving observability and reducing risk. Essentially, it acts as a single point of control for all your OpenTelemetry data.