Backport GenAI

[michaelgsharp]

…270)

• leverage MEAI abstraction

• Update src/Microsoft.ML.GenAI.LLaMA/Llama3CausalLMChatClient.cs

• Update src/Microsoft.ML.GenAI.LLaMA/Llama3CausalLMChatClient.cs

• Update src/Microsoft.ML.GenAI.Phi/Phi3/Phi3CausalLMChatClient.cs

• fix comments

• Update Microsoft.ML.GenAI.Core.csproj

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• You have included any necessary tests in the same PR.

[codecov]

Codecov Report

Attention: Patch coverage is 33.33333% with 152 lines in your changes missing coverage. Please review.

Project coverage is 68.84%. Comparing base (2a879f6) to head (6ed398e).
Report is 1 commits behind head on release/4.0.

Files with missing lines	Patch %	Lines
...rosoft.ML.GenAI.Core/CausalLMPipelineChatClient.cs	0.00%	48 Missing ⚠️
...osoft.ML.GenAI.Phi/Phi3/Phi3ChatTemplateBuilder.cs	43.83%	35 Missing and 6 partials ⚠️
...crosoft.ML.GenAI.LLaMA/Llama3CausalLMChatClient.cs	0.00%	24 Missing ⚠️
...rosoft.ML.GenAI.Phi/Phi3/Phi3CausalLMChatClient.cs	0.00%	24 Missing ⚠️
...soft.ML.GenAI.LLaMA/Llama3_1ChatTemplateBuilder.cs	69.23%	5 Missing and 3 partials ⚠️
...c/Microsoft.ML.GenAI.Phi/Phi3/Phi3CausalLMAgent.cs	60.00%	6 Missing ⚠️
...enAI.Phi/Phi3/Phi3CausalLMChatCompletionService.cs	83.33%	1 Missing ⚠️

Additional details and impacted files

@@               Coverage Diff               @@
##           release/4.0    #7298      +/-   ##
===============================================
- Coverage        68.87%   68.84%   -0.04%     
===============================================
  Files             1469     1473       +4     
  Lines           273989   274159     +170     
  Branches         28389    28420      +31     
===============================================
+ Hits            188718   188746      +28     
- Misses           77963    78095     +132     
- Partials          7308     7318      +10     

Flag	Coverage Δ
Debug	68.84% <33.33%> (-0.04%)	⬇️
production	63.29% <30.27%> (-0.04%)	⬇️
test	89.18% <100.00%> (+<0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
...enAI.Phi/Phi3/Phi3CausalLMTextGenerationService.cs	35.71% <100.00%> (+1.56%)	⬆️
...st/Microsoft.ML.GenAI.LLaMA.Tests/LLaMA3_1Tests.cs	94.73% <100.00%> (+0.79%)	⬆️
...enAI.Phi/Phi3/Phi3CausalLMChatCompletionService.cs	61.90% <83.33%> (-3.10%)	⬇️
...c/Microsoft.ML.GenAI.Phi/Phi3/Phi3CausalLMAgent.cs	52.00% <60.00%> (-4.72%)	⬇️
...soft.ML.GenAI.LLaMA/Llama3_1ChatTemplateBuilder.cs	68.83% <69.23%> (+0.20%)	⬆️
...crosoft.ML.GenAI.LLaMA/Llama3CausalLMChatClient.cs	0.00% <0.00%> (ø)
...rosoft.ML.GenAI.Phi/Phi3/Phi3CausalLMChatClient.cs	0.00% <0.00%> (ø)
...osoft.ML.GenAI.Phi/Phi3/Phi3ChatTemplateBuilder.cs	43.83% <43.83%> (ø)
...rosoft.ML.GenAI.Core/CausalLMPipelineChatClient.cs	0.00% <0.00%> (ø)

... and 6 files with indirect coverage changes