Mark null-propagating math functions as strict

[lyne7-sc]

Which issue does this PR close?

• Closes #.

Rationale for this change

This PR follows up on #23148, which introduced strictness metadata for scalar UDF NULL propagation and used it during outer join elimination. It marks built-in math functions that propagate NULL inputs as strict, allowing the optimizer to recognize more null-rejecting predicates and simplify the corresponding outer joins.

What changes are included in this PR?

• Extend the math UDF helper macros to support the is_strict property.
• Mark null-propagating math scalar functions as strict.
• Add unit tests covering:
  • supported math functions;
  • unary and binary variants;
  • every combination of NULL arguments;
  • non-NULL inputs.
• Add SQL logic tests showing that strict math predicates enable outer join elimination for:
  • LEFT, RIGHT, and FULL joins;
  • unary and binary functions;
  • nullable arguments in either position;
  • binary function arguments coming from both sides of a join.

Are these changes tested?

Yes. Unit tests cover NULL propagation for the affected math functions, and SLTs verify the resulting outer join simplifications.

Are there any user-facing changes?

Yes. Queries containing null-rejecting predicates over math functions may now produce more efficient plans by simplifying eligible outer joins.

There are no public API changes.