Parse errors from Bedrock properly

[tpaulshippy]

Turns out, the response body from Bedrock looks like this:

{"message":"messages.1.content: Input should be a valid list"}

[codecov]

Codecov Report

Attention: Patch coverage is 62.50000% with 3 lines in your changes missing coverage. Please review.

Project coverage is 92.42%. Comparing base (d3c01f1) to head (159c03c).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
lib/ruby_llm/providers/bedrock.rb	62.50%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #94      +/-   ##
==========================================
- Coverage   92.51%   92.42%   -0.09%     
==========================================
  Files          72       72              
  Lines        2697     2705       +8     
  Branches      383      387       +4     
==========================================
+ Hits         2495     2500       +5     
- Misses        202      205       +3     

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[crmne]

Thanks @tpaulshippy you've inspired 535c9e1