Schema-qualify 62 unqualified references in 24 function bodies (enamel_025)

Qualification migration completing the search_path hardening chain: 023A2/023A/024 pinned every public function, 025 qualifies the bodies so the pin is not load-bearing at call time. Derivation by reading 87 reference sites; two shared derivation/guard blind spots found and structurally repaired (strip-order, whole-line negative predicate).