KAFKA-20150: Add Structurizr scaffolding for C4 Diagrams

[sujayopensource]

Summary

• Add Structurizr scaffolding and documentation for creating C4 architecture diagrams
• Provide a ready-to-use Kafka architecture model as a starting point
• Document installation options, DSL reference, and CI/CD integration patterns

Test plan

• Validate workspace.dsl syntax: docker run --rm -v $(pwd)/docs/architecture/structurizr:/root/data -w /root/data structurizr/cli validate
  -workspace workspace.dsl
• Run Structurizr Lite locally and verify diagrams render correctly
• Review documentation for accuracy and completeness

Files Added
File: docs/architecture/Integration_of_Structurizr_for_C4_Diagrams.md
Description: Comprehensive guide covering C4 model, Structurizr DSL, installation, examples, and best practices
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File: docs/architecture/structurizr/workspace.dsl
Description: Structurizr DSL workspace defining Kafka architecture (brokers, controllers, APIs, Connect, Streams)
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File: docs/architecture/structurizr/workspace.json
Description: Generated JSON representation of the workspace
Quick Start

cd docs/architecture/structurizr
docker run -it --rm -p 8080:8080 -v $(pwd):/usr/local/structurizr structurizr/lite

Open http://localhost:8080