Function simplify_expression 

pub fn simplify_expression(expr: &TLExpr) -> TLExpr

Simplify a logical expression using standard equivalences

Applies the following transformations:

• Constant folding: Add(Constant(a), Constant(b)) => Constant(a + b)
• Identity laws: AND(x, true) => x, OR(x, false) => x
• Annihilation laws: AND(x, false) => false, OR(x, true) => true
• Double negation elimination: NOT(NOT(x)) => x
• Idempotent laws: AND(x, x) => x, OR(x, x) => x
• Absorption laws: AND(x, OR(x, y)) => x
• De Morgan’s laws: NOT(AND(x, y)) => OR(NOT(x), NOT(y))