Phi-3.5-MoE support

[okaneyo]

Add support for this incredible model

[johnmai-dev]

ChatMLX mainly relies on the support provided by MLX Swift Examples.

Add Phi 3.5 MoE ml-explore/mlx-swift-examples#116

I will update promptly after this PR is merged.

[DePasqualeOrg]

@okaneyo, you can test my attempt to implement Phi 3.5 MoE in ml-explore/mlx-swift-examples#116 and tell me if it works. My MacBook unfortunately doesn't have enough RAM for me to test it myself.

[johnmai-dev]

@okaneyo, you can test my attempt to implement Phi 3.5 MoE in ml-explore/mlx-swift-examples#116 and tell me if it works. My MacBook unfortunately doesn't have enough RAM for me to test it myself.

Thank you! @DePasqualeOrg