Remove SPARK and add back direct matrix evaluation

[batmendbar]

No description provided.

[veljkovranic]

LGTM

[shreyas-londhe]

@batmendbar Can you make sure CI passes. We can merge then.

[codspeed-hq]

CodSpeed WallTime Performance Report

Merging #141 will improve performances by ×4.4

_{Comparing move-spark (165e2f3) with main (19c3141)}

⚠️ Unknown Walltime execution environment detected

Using the Walltime instrument on standard Hosted Runners will lead to inconsistent data.

For the most accurate results, we recommend using CodSpeed Macro Runners: bare-metal machines fine-tuned for performance measurement consistency.

Summary

⚡ 3 improvements
✅ 32 untouched benchmarks

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
⚡	prove_poseidon_1000	26.9 s	6.1 s	×4.4
⚡	prove_poseidon_1000_with_io	28.6 s	7.8 s	×3.7
⚡	verify_poseidon_1000	3.2 ms	1.6 ms	+99.96%

[ashpect]

@veljkovranic Just curious, was there an unresolved blocker that required commenting out the compiler tests to keep CI passing ?