doc: add GenAI cheat sheet

[ykharkov]

Issue #, if available:

Description of changes:
Added .md cheat sheet file tailored (and prompt-optimized) for GenAI applications.

Testing done:

Merge Checklist

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (2f02107) to head (02b1440).
Report is 49 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##              main     #1007   +/-   ##
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  Coverage   100.00%   100.00%           
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  Files          135       135           
  Lines         8941      8949    +8     
  Branches      2008      2011    +3     
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+ Hits          8941      8949    +8     

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[rmshaffer]

@ykharkov thank you for raising this PR. A few questions:

1. Could you clarify how this relates to feat: publish a cheat sheet via github pages #995, which also adds this file? Should we remove it from that PR, or should these be rolled together?
2. What is the intended usage of this file? Is there something actively consuming it?
3. Is there a mechanism we can use to ensure that this file stays up-to-date as the SDK changes?