feat: upgrade to CBL C SDK 3.1.0

[blaugold]

No description provided.

[codecov]

Codecov Report

Merging #478 (6a4ed3f) into main (af7f66d) will decrease coverage by 0.48%.
The diff coverage is 28.57%.

❗ Current head 6a4ed3f differs from pull request most recent head 2aeec52. Consider uploading reports for the commit 2aeec52 to get more accurate results

@@            Coverage Diff             @@
##             main     #478      +/-   ##
==========================================
- Coverage   89.18%   88.71%   -0.48%     
==========================================
  Files         143      143              
  Lines       10081    10170      +89     
==========================================
+ Hits         8991     9022      +31     
- Misses       1090     1148      +58     

Flag	Coverage Δ
e2e.cbl	88.88% <0.00%> (+0.05%)	⬆️
unit.cbl	2.31% <ø> (+<0.01%)	⬆️
unit.cbl_dart	15.46% <28.57%> (-0.23%)	⬇️
unit.cbl_generator	31.23% <0.00%> (+0.01%)	⬆️
unit.cbl_sentry	8.89% <0.00%> (-0.01%)	⬇️

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Impacted Files	Coverage Δ
packages/cbl_ffi/lib/src/fleece.dart	85.79% <ø> (-6.42%)	⬇️
packages/cbl_dart/lib/src/package.dart	77.19% <28.57%> (-15.92%)	⬇️

... and 3 files with indirect coverage changes