[Refactoring] deduceWildHelper and its caller side
fix Issue 12880 - Wrong IFTI for string.init argument

Consider matching between e->type->mod to tparam->mod in deduceExpType
fix Issue 12876 - Implicit cast of array slice to fixed-size array for templates too
Merge pull request #3650 from 9rnsr/fix12876

Issue 12876 - Implicit cast of array slice to fixed-size array for templates too