feat: Optimize merging numeric values

[jfecher]

Description

Problem*

Resolves

Summary*

Found while working on #4716

This reduces the size of the circuit in #4688 to just 19725 constraints (2314 acir opcodes). Forgot my local version of the test program was modified.

Additional Context

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.

[vezenovm]

LGTM

[jfecher]

The difference I was seeing in constraint count was because I forgot I had locally changed the test file.
The CI of this PR indicates it also has no optimization changes elsewhere so I'm closing it.