feat: rewrite constraints on binary instructions in terms of their inputs

[TomAFrench]

…

Description

Problem*

Resolves

Summary*

This PR is blocked by #4065 and #4060 as otherwise we get a large number of duplicated constraints from multiple constraints being decomposed into the same base set of constraints.

Additional Context

Documentation*

Check one:

• No documentation needed.
• Documentation included in this PR.
• [Exceptional Case] 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: ca0f57c326d1c6c26c17e90675ef78e0e52b0c9b, compared to commit: 49e1b0c0d45565f3e87469b77f2fef0c283f6ea1

🧾 Summary (10% most significant diffs)

Program	ACIR opcodes (+/-)	%	Circuit size (+/-)	%
references	+40 ❌	+666.67%	+37 ❌	+176.19%
slice_dynamic_index	+238 ❌	+18.00%	+452 ❌	+6.59%

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Full diff report 👇

Program	ACIR opcodes (+/-)	%	Circuit size (+/-)	%
references	46 (+40)	+666.67%	58 (+37)	+176.19%
slice_dynamic_index	1,560 (+238)	+18.00%	7,307 (+452)	+6.59%
slices	417 (+106)	+34.08%	3,531 (+115)	+3.37%
7_function	256 (+22)	+9.40%	3,027 (+20)	+0.67%
u128	781 (-1)	-0.13%	4,782 (-1)	-0.02%