fix: do not simplify call-data values

[guipublic]

Description

Problem*

Resolves #9984

Summary*

Input witness are not simplified in ACIR generation

Additional Context

The issue is about potential issues with Databus due to simplifications passes.
However, the databus values need to be updated during the various ssa passes because instructions may be transformed (e.g during unrolling) and mapped to equivalent instructions but with updated IDs.
It turns out that these transformations are correct within SSA passes because the databus ‘call-data’ is defined at the beginning of ssa generation. When a value is simplified, subsequent uses of the value will be replaced, but not its definition.
As a result, values in the call-data array may be updated, but not simplified.

On the other hand on ACIR side, the databus is initialized after ACIR generation, which creates witness for constant values and may replace call-data parameters with these constant witness.
We may want to do the same as with SSA, i.e generate the call-data array before ACIR generation, but this is not always possible, because call-data SSA values can be ‘array-get’ values which need to be properly resolved by ACIR generation.
Another possibility could be to generate the call-data array during ACIR generation but it would make the ACIR generation more inter-dependent to the databus.
I ended up with a simpler solution which avoid to simplify input witness with constant values. Indeed, call-data values are all inputs from main.
A small refinement could be to do this only for call-data parameters, but having this logic for all the inputs looks more coherent to me.

Documentation*

Check one:

• No documentation needed.
• Documentation included in this PR.
• [For Experimental Features] Documentation to be submitted in a separate PR.

PR Checklist*

• I have tested the changes locally.
• I have formatted the changes with Prettier and/or cargo fmt on default settings.

[github-actions]

Changes to circuit sizes

Generated at commit: 1350dd6b8bfa83bfdae4d1dbb50acb4e8ad60746, compared to commit: 1324e732b92ee9624307ee226ffeed01610287a6

🧾 Summary (10% most significant diffs)

Program	ACIR opcodes (+/-)	%	Circuit size (+/-)	%
global_nested_array_call_arg_regression	+4 ❌	+40.00%	+2,747 ❌	+3309.64%
nested_array_call_arg_regression	+4 ❌	+40.00%	+2,747 ❌	+3309.64%

---

Full diff report 👇

Program	ACIR opcodes (+/-)	%	Circuit size (+/-)	%
global_nested_array_call_arg_regression	14 (+4)	+40.00%	2,830 (+2,747)	+3309.64%
nested_array_call_arg_regression	14 (+4)	+40.00%	2,830 (+2,747)	+3309.64%
slices	323 (0)	0.00%	3,936 (+1)	+0.03%
conditional_1	2,653 (+35)	+1.34%	17,416 (0)	0.00%

[github-actions]

⚠️ Performance Alert ⚠️

Possible performance regression was detected for benchmark 'Test Suite Duration'.
Benchmark result of this commit is worse than the previous benchmark result exceeding threshold 1.20.

Benchmark suite	Current: 8b547ef	Previous: 1324e73	Ratio
test_report_zkpassport_noir_rsa_	2 s	1 s	2

This comment was automatically generated by workflow using github-action-benchmark.

CC: @TomAFrench

[github-actions]

⚠️ Performance Alert ⚠️

Possible performance regression was detected for benchmark 'ACVM Benchmarks'.
Benchmark result of this commit is worse than the previous benchmark result exceeding threshold 1.20.

Benchmark suite	Current: df89010	Previous: 39f193c	Ratio
perfectly_parallel_batch_inversion_opcodes	2779925 ns/iter (± 3766)	2254940 ns/iter (± 1115)	1.23

This comment was automatically generated by workflow using github-action-benchmark.

CC: @TomAFrench

[github-actions]

⚠️ Performance Alert ⚠️

Possible performance regression was detected for benchmark 'Execution Time'.
Benchmark result of this commit is worse than the previous benchmark result exceeding threshold 1.20.

Benchmark suite	Current: 8b547ef	Previous: 1324e73	Ratio
rollup-checkpoint-merge	0.004 s	0.003 s	1.33
sha512-100-bytes	0.065 s	0.048 s	1.35

This comment was automatically generated by workflow using github-action-benchmark.

CC: @TomAFrench

[github-actions]

⚠️ Performance Alert ⚠️

Possible performance regression was detected for benchmark 'Compilation Time'.
Benchmark result of this commit is worse than the previous benchmark result exceeding threshold 1.20.

Benchmark suite	Current: 3610282	Previous: 9808525	Ratio
sha512-100-bytes	1.903 s	1.572 s	1.21

This comment was automatically generated by workflow using github-action-benchmark.

CC: @TomAFrench