add-propagator-chirho

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Add a new propagator to propagators-chirho: $ARGUMENTS

Instructions

1. Analyze the requested propagator type and its bidirectional semantics
2. Determine if it fits existing macros:

- ternarypropagatorchirho! - for a op b = c patterns - binarypropagatorchirho! - for unary a = b patterns - comparisonpropagatorchirho! - for max/min style patterns

1. Add the propagator to src/propagator_chirho.rs following existing patterns
2. Add corresponding method to ConstraintSystemChirho in src/constraintsystemchirho.rs
3. If arena feature is used, add to src/arena_chirho.rs as well
4. Add unit tests for the new propagator
5. Update CHANGELOG.md with the new propagator under [Unreleased]
6. Run tests to verify: cargo test

Naming Convention

• Struct: {Name}Chirho (e.g., ModuloChirho)
• Install method: install_chirho
• ConstraintSystem method: add{name}chirho (e.g., addmodulochirho)
• All fields/variables use _chirho suffix per project convention