chore: Remove Type from Value, and remove ctrl_typevars

[jfecher]

Description

Problem*

Summary*

Another step towards removing ValueId.

Removes Type from the Value enum to make Values copyable by moving types to be stored in Instructions when they weren't before. This means every instruction knows its result type(s) and ctrl_typevars are never needed

Unlike #6769, this PR is a draft because I need to check performance - without the larger change to use a Value enum instead of ValueIds, this PR may result in worse performance alone.

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.

[github-actions]

Changes to Brillig bytecode sizes

Generated at commit: 0b564760891e7dc8d547d919f14d3415057ee92e, compared to commit: f6957faf50025afc053a32d86398d0823253066b

🧾 Summary (10% most significant diffs)

Program	Brillig opcodes (+/-)	%
to_le_bytes	+4 ❌	+2.99%

---

Full diff report 👇

Program	Brillig opcodes (+/-)	%
to_le_bytes	138 (+4)	+2.99%

[github-actions]

Peak Memory Sample

Program	Peak Memory	%
keccak256	78.39M	0%
workspace	121.67M	0%
regression_4709	305.28M	3%
ram_blowup_regression	2.44G	0%
private-kernel-tail	209.24M	0%
private-kernel-reset	861.86M	0%
private-kernel-inner	307.71M	0%
parity-root	174.80M	0%

[github-actions]

Compilation Sample

Program	Compilation Time	%
sha256_regression	0m1.563s	9%
regression_4709	0m1.478s	-3%
ram_blowup_regression	0m17.829s	7%
private-kernel-tail	0m1.526s	21%
private-kernel-reset	0m9.419s	9%
private-kernel-inner	0m2.373s	0%
parity-root	0m0.922s	-12%
noir-contracts	2m36.715s	-6%