#20 return-type: when a CallScript/CallShared result is assigned directly into
a typed local declaration (optionally awaited, optionally via an Instance./
Scripts./Parent./Children["x"]. receiver), compare the LHS declared type
against the target script's declared ReturnDefinition and flag clear
cross-category mismatches (ReturnTypeMismatch). Previously BuildReturnMap was
built but never read.
#21 argument-type: positional call arguments are now split (paren/brace/bracket
+ string-literal aware) and each literal-inferable argument is checked against
the target's declared parameter type (ParameterMismatch), not just the count.
Conservative — only CLEAR primitive mismatches (String/Integer/Float/Boolean)
are flagged; Integer<->Float widening is tolerated. Unknown/Object/List
declarations, var/untyped/unused/expression-embedded assignments, and
non-literal arguments (variables, member access, method/await chains, casts,
object/array initializers, compound or concatenated expressions, interpolated
strings) are never flagged. Inference limits documented in code.
Adds 16 SemanticValidatorTests covering mismatch detection, correct-call pass,
and the dynamic/unknown no-false-positive cases.
Joseph Doherty
958229e1f8