[WIP] Update static collections

[esoteric-ephemera]

Updating data models / fields for static collections per discussion with @tsmathis:

• Data schema for Atlas search results in Synthesis data
• Ensure structure field in surface properties is structure and not CIF str
• Replace grain boundaries cif field with structure

[codecov-commenter]

Codecov Report

❌ Patch coverage is 72.72727% with 9 lines in your changes missing coverage. Please review.
✅ Project coverage is 86.03%. Comparing base (7eb5760) to head (038726f).

Files with missing lines	Patch %	Lines
emmet-core/emmet/core/grain_boundary.py	60.00%	6 Missing ⚠️
emmet-core/emmet/core/surface_properties.py	70.00%	3 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #1401      +/-   ##
===========================================
- Coverage    86.06%   86.03%   -0.03%     
===========================================
  Files          243      243              
  Lines        19373    19399      +26     
===========================================
+ Hits         16673    16690      +17     
- Misses        2700     2709       +9     

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