Serialize let bindings

[saulshanabrook]

Closes #376 by storing the let bindings on the serialized format.

This also will show them in the visualizer now:

cargo run -- tests/web-demo/eqsat-basic.egg --to-svg

Please review and merge egraphs-good/egraph-serialize#23 first and then I can update the dep here to pull from main.

[codspeed-hq]

CodSpeed Performance Report

Merging #701 will not alter performance

_{Comparing saulshanabrook:let-bindings-again (cc726e9) with main (5678c6c)¹}

Summary

✅ 20 untouched
⏩ 190 skipped²

Footnotes

1. No successful run was found on main (cc726e9) during the generation of this report, so 5678c6c was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

2. 190 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[saulshanabrook]

This is now ready for review now that egraph-serialize has a new version.

[Copilot]

Pull Request Overview

This PR replaces the ignore_viz field with let_binding to properly serialize let bindings in the egraph output format, enabling them to be displayed in the visualizer.

Key Changes:

• Renamed ignore_viz to let_binding throughout the codebase to better reflect its semantic purpose
• Modified serialization logic to store let bindings as metadata on e-classes rather than filtering them out
• Updated egraph-serialize dependency from git branch to version 0.3

Reviewed Changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/ast/mod.rs	Renamed ignore_viz field to let_binding in FunctionDecl struct and its constructors
src/ast/remove_globals.rs	Updated field name from ignore_viz to let_binding for global removal logic
src/serialize.rs	Refactored serialization to collect and store let bindings in class metadata instead of filtering them
src/typechecking.rs	Updated field reference from ignore_viz to let_binding
Cargo.toml	Changed egraph-serialize from git dependency to version 0.3

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[saulshanabrook]

@codex review

[yihozhang]

Missed this PR, sorry!

This looks like a breaking change because the public field ignore_viz is renamed. Maybe we should find a way to track when a breaking change is introduced?

[saulshanabrook]

This looks like a breaking change because the public field ignore_viz is renamed. Maybe we should find a way to track when a breaking change is introduced?

I added an entry to the changelog that makes it explicit it's breaking.