Post Reorg Tweaks

[brett0000FF]

What does this PR do? What is the motivation?

• Rename OTel API -> OTel API with Datadog SDK
• Rename Environment Variables -> Configuration
• Rename Direct OTLP Ingest -> Agentless Deployment
• Add structure to Getting Started for DD Example or OTel Demo

Merge instructions

Merge readiness:

• Ready for merge

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Additional notes

[github-actions]

Preview links (active after the build_preview check completes)

New or renamed files

• https://docs-staging.datadoghq.com/brett.blue/post-reorg-tweaks/opentelemetry/getting_started

Renamed files

• https://docs-staging.datadoghq.com/brett.blue/post-reorg-tweaks/opentelemetry/setup/agentless/
• https://docs-staging.datadoghq.com/brett.blue/post-reorg-tweaks/opentelemetry/setup/agentless/logs
• https://docs-staging.datadoghq.com/brett.blue/post-reorg-tweaks/opentelemetry/setup/agentless/metrics
• https://docs-staging.datadoghq.com/brett.blue/post-reorg-tweaks/opentelemetry/setup/agentless/traces

Modified Files

• https://docs-staging.datadoghq.com/brett.blue/post-reorg-tweaks/opentelemetry/
• https://docs-staging.datadoghq.com/brett.blue/post-reorg-tweaks/opentelemetry/setup/