feat: individual gpu settings

[Misieq01]

Continuation of #1054

Important note

It Requires versions 0.1.19 of gpuminer. From what i saw release for this version didn't passed so to work with this PR or test it its required to build gpuminer from main locally and replace binaries until version 0.1.19 is released

[ Summary ]

• Expanded Custom mode modal to take into account multiple gpu devices
• Expanded and adjusted max_gpu_threads and correlated fields on frontend and backend
• Fixed parsing gpu_status.json in gpu_miner
• Changed passed value to grid_size to include multiple gpu devices

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[ What is left to do ]

• Remove unnecessary console.logs
• Cleanup code
• Make adjustments to UI if needed
• Test it on wider range of devices