refactor(cli): context providers use dedicated, provided messaging class

[mrgrain]

Introduces a dedicated messaging interface for Context Providers. This is a reduced interface to allow Context Providers send debug messages and in rare cases info messages.

Use of ioHelper in the provideContextValues function is currently still optional until the CloudExecutable supports it as well.

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By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 91.07143% with 10 lines in your changes missing coverage. Please review.

Project coverage is 85.09%. Comparing base (2dc5a56) to head (ac85e9a).

Files with missing lines	Patch %	Lines
packages/aws-cdk/lib/context-providers/index.ts	85.96%	8 Missing ⚠️
packages/aws-cdk/lib/api/cxapp/cloud-executable.ts	0.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #277      +/-   ##
==========================================
- Coverage   85.18%   85.09%   -0.09%     
==========================================
  Files         221      221              
  Lines       36610    36675      +65     
  Branches     4440     4432       -8     
==========================================
+ Hits        31186    31210      +24     
- Misses       5325     5369      +44     
+ Partials       99       96       -3     

Flag	Coverage Δ
suite.unit	85.09% <91.07%> (-0.09%)	⬇️

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