Optimize comparison operators

[Rigidity]

Note

Medium Risk
Changes core compiler lowering for ordering operators used throughout Rue programs; behavior should be equivalent but CLVM shape and costs differ, so regression risk is in edge cases for int/bytes compares.

Overview
>= / <= (int and bytes) in lower.rs no longer lower to any(>, =); they now use not(<) or not(>), cutting extra Eq/Any nodes from generated CLVM while keeping the same semantics.

Environment::tree sorts symbols by reference count with sort_by_key(|b| Reverse(b.1)) instead of a manual sort_by on counts.

The release bumps workspace crates 0.8.4 → 0.8.5, adds rust-toolchain.toml (Rust 1.97.0), expands comparison assertions in operators.rue, and refreshes operators.yaml program/cost snapshots.

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