work on Field class

[aperijake]

• used field class in solver
• add more tests
• fix some issues with running on the GPU

[trunk-io]

⏱️ 3h 32m total CI duration on this PR

Slowest 15 Jobs	Cumulative Duration	Recent Runs
Build Release, GPU	1h 6m	🟩 🟩
Build Debug, GPU	1h 2m	🟩 🟩
Build Debug, Code Coverage	20m	🟩 🟩
Build Release	15m	🟩 🟩
Build Debug	15m	🟩 🟩
Regression Test Release, GPU	5m	🟩 🟩
Regression Test Debug, GPU	5m	🟩 🟩
Regression Test Debug	4m	🟩 🟩
Test Debug, GPU	4m	🟩 🟩
Test Release, GPU	4m	🟩 🟩
Setup	4m	🟩 🟩
Test Debug	3m	🟩 🟩
Test Release	2m	🟩 🟩
Teardown	2m	🟩 🟩
Analyze (javascript-typescript)	1m	🟩

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