Add initial Logs Bridge API scaffolding

[MrAlias]

Part of #3827

Add the initial scaffolding the logs bridge API will be built from. This is a copy of all the things discussed in the logs design doc. All implementation details have been omitted and documented with "TODO"s that link to the issue tracking the work.

Blocks:

• Document the log package #4908
• Add the log/embedded package #4909
• Add the log/noop package #4910
• Implement the Logger configuration #4911
• Add tests for the Severity type #4912
• Implement the Record type #4913
• Implement the Value and KeyValue types #4914
• Add benchmarks to log package #4915
• Add allocation unit tests to log package #4916

[codecov]

Codecov Report

Attention: 58 lines in your changes are missing coverage. Please review.

Comparison is base (02b6123) 82.7% compared to head (7411393) 82.4%.

Additional details and impacted files

@@           Coverage Diff           @@
##            main   #4907     +/-   ##
=======================================
- Coverage   82.7%   82.4%   -0.3%     
=======================================
  Files        232     237      +5     
  Lines      18916   18974     +58     
=======================================
+ Hits       15649   15651      +2     
- Misses      2977    3033     +56     
  Partials     290     290             

Files	Coverage Δ
log/logger.go	0.0% <0.0%> (ø)
log/kind_string.go	0.0% <0.0%> (ø)
log/severity_string.go	0.0% <0.0%> (ø)
log/record.go	0.0% <0.0%> (ø)
log/keyvalue.go	0.0% <0.0%> (ø)

... and 1 file with indirect coverage changes

[dashpole]

lgtm after question is resolved

[XSAM]

🚀