Implement Reddit feedback/ideas

[rennf93]

Description

Adds 5 new features to fastapi-guard v4.4.0: configurable cloud IP refresh interval, change detection logging for cloud refreshes, context-aware suspicious pattern detection, structured JSON logging, and per-provider last_updated timestamps on CloudManager. Both example apps (simple_app, advanced_app) are updated to showcase all new features via SecurityConfig options and a new /admin/cloud-status endpoint.

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Related Issue

N/A

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Motivation and Context

• Cloud IP refresh was hardcoded at 1 hour with no visibility into what changed — operators need tunable intervals and diff logging.
• The detection engine evaluated every pattern against every input source, causing false positives (e.g., SQL patterns matching URL paths). Context tagging fixes this.
• Plain text logs don't integrate with log aggregation systems (ELK, Datadog, CloudWatch). Structured JSON output enables this.
• No way to know when each cloud provider's IP ranges were last refreshed — last_updated makes this observable.

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Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation change
• Performance improvement
• Code cleanup or refactoring

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How Has This Been Tested

• tests/test_features/test_configurable_cloud_refresh.py: validates interval range enforcement, propagation to Redis TTL, and refresh behavior
• tests/test_features/test_context_aware_detection.py: verifies patterns only match relevant input contexts and skip irrelevant ones
• tests/test_features/test_structured_json_logging.py: confirms JSON formatter output structure and fallback to text format
• tests/test_features/test_last_updated_cloud.py: checks per-provider datetime tracking after refresh
• All existing tests pass with no regressions

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Screenshots (if appropriate)

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Checklist

• My code follows the code style of this project (Mypy, Ruff)
• I have added tests to cover my changes
• All new and existing tests passed
• My change requires a change to the documentation
• I have updated the documentation accordingly
• I have checked that my changes don't introduce any new warnings or errors
• I have updated the version number if necessary
• I have added any new dependencies to the appropriate requirements file