feat: Adds validation_state to the json reports from the Reader

[gpeacock]

This is also a cleanup of the new API, removing ManifestStore, ManifestStoreReport, and Store from the public API unless the v1_api feature is used.
These are steps toward a version 1.0 SDK.

[codecov]

Codecov Report

Attention: Patch coverage is 74.90909% with 69 lines in your changes missing coverage. Please review.

Project coverage is 78.74%. Comparing base (bd737c8) to head (c1303e0).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
sdk/src/reader.rs	72.61%	43 Missing ⚠️
sdk/src/manifest_store_report.rs	10.00%	9 Missing ⚠️
make_test_images/src/compare_manifests.rs	0.00%	7 Missing ⚠️
sdk/src/store.rs	86.20%	4 Missing ⚠️
sdk/src/validation_results.rs	94.44%	3 Missing ⚠️
sdk/src/validation_status.rs	70.00%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #930      +/-   ##
==========================================
- Coverage   78.94%   78.74%   -0.21%     
==========================================
  Files         147      147              
  Lines       34842    34965     +123     
==========================================
+ Hits        27507    27534      +27     
- Misses       7335     7431      +96     

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[tmathern]

Out of an abundacne of caution, I would suggest to verify this does not break c2pa-c and c2pa-python before emrging it (breaking the builds and/or the tests).

And even if it breaks something, then we'd know what to fix too.

[gpeacock]

I build and ran tests using this branch with c2pa-c and c2pa-python, everything built without errors and all tests passed.