feat: support phi3.5 moe

[drbh]

This is a work in progress PR to add support for microsoft/Phi-3.5-MoE-instruct

TODO

• add phi 3.5 to ModelType
• load weights into memory
• prefer moe over mlp in layers
• enable long/short rope scaling
• validate scaling logic
• ensure layer logic is correct
• ensure no regressions on existing phi models
• identify issue with allocating graphs
• refactor/cleanup/add tests

[HuggingFaceDocBuilderDev]

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[drbh]

This PR adds support for phi 3.5 moe, and improves the chat endpoint to assume greedy generation unless the temp is explicitly set by the user in the request (this helped align the expected output from phi with the reference impl).

Start phi3.5moe

text-generation-launcher \
  --model-id microsoft/Phi-3.5-MoE-instruct \
  --num-shard 4 \
  --cuda-graphs 1,2 \
  --trust-remote-code

send a request

curl 127.0.0.1:3000/generate -X POST \
  -H 'Content-Type: application/json' \
  -d '{
    "inputs": "Hello who are you?",
    "parameters": {
      "max_new_tokens": 20
    }
  }'

response

{
    "generated_text": " I'm an artificial intelligence developed by Microsoft to assist with a variety of tasks and provide information."
}