WIP: replace register-alloc with purely stack-based translation

[Robbepop]

Closes #1484.

[codecov]

Codecov Report

Attention: Patch coverage is 3.87289% with 968 lines in your changes missing coverage. Please review.

Project coverage is 66.87%. Comparing base (d63125c) to head (e4dd0e0).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...mi/src/engine/translator/translator2/simd/visit.rs	0.00%	256 Missing ⚠️
...s/wasmi/src/engine/translator/translator2/visit.rs	0.00%	213 Missing ⚠️
...src/engine/translator/translator2/stack/control.rs	0.00%	115 Missing ⚠️
...rc/engine/translator/translator2/stack/operands.rs	0.00%	115 Missing ⚠️
...smi/src/engine/translator/translator2/stack/mod.rs	0.00%	87 Missing ⚠️
...src/engine/translator/translator2/stack/operand.rs	0.00%	46 Missing ⚠️
...tes/wasmi/src/engine/translator/translator2/mod.rs	0.00%	42 Missing ⚠️
...mi/src/engine/translator/translator2/layout/mod.rs	0.00%	35 Missing ⚠️
...src/engine/translator/translator2/layout/consts.rs	0.00%	32 Missing ⚠️
.../src/engine/translator/translator2/stack/locals.rs	72.22%	15 Missing ⚠️
... and 2 more

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1512      +/-   ##
==========================================
- Coverage   70.69%   66.87%   -3.83%     
==========================================
  Files         177      188      +11     
  Lines       16585    17592    +1007     
==========================================
+ Hits        11725    11764      +39     
- Misses       4860     5828     +968     

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