docs: clarify intended usage and Docker vs Edge guidance

[omwanere]

This PR clarifies the intended usage of the engine, adds a decision guide
for new projects, and explains Docker vs Edge usage as requested in #276.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

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📝 Walkthrough

Summary by CodeRabbit

• Documentation
  • Added guidance on intended usage patterns for the Stripe data engine, including supported use cases (data synchronization, analytics, webhook processing) and unsupported scenarios.
  • Included deployment decision guidance for Docker and Edge environments with usage examples and performance considerations.

Walkthrough

A new documentation file was added that provides usage guidance for the Stripe data engine. The document outlines the engine's intended purpose for data ingestion, synchronization, and analytics following Stripe events. It specifies appropriate use cases such as syncing data to databases, processing webhooks, and building analytics dashboards, while clarifying non-use cases like payment acceptance and checkout flows. The documentation includes a decision table for when to use the engine versus alternative approaches, distinguishes between Docker and Edge deployment scenarios with respective criteria, and provides example usage patterns with considerations for deployment architecture and processing latency.

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_{Comment @coderabbitai help to get the list of available commands and usage tips.}