metal: add CONV_3D (#19927)
* Apply suggestions from code review
Co-authored-by: Georgi Gerganov <ggerganov@gmail.com>
* metal:add conv_3d backend
Rebased with master and resolved conflicts.
* Resolved issues related to changes in variable names
* kernel void kernel_upscale_bilinear_f32 was missing in my branch, added back, should pass all tests now
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Co-authored-by: Georgi Gerganov <ggerganov@gmail.com>
