ref(docs): restructure core infrastructure section for improved readability

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• Rewording and restructuring of multiple sections for better readability and brevity.
• Addition of new sub-sections and bullet points to highlight key practices and tools.
• Emphasis on proactive monitoring, integration, collaboration, and environment parity.
• Introduction of new concepts like chaos engineering, ephemeral test environments, and test data management.
• Removal of extensive verbose explanations, replacing them with concise summaries and actionable tips.