test(drawdb): add test for converting column types with modifiers

* Implement tests to ensure explicit type modifiers are preserved during conversion.
* Validate behavior for varchar, numeric, and custom vector types.

pkg/writers/graphql/type_mapping.go

@@ -4,6 +4,7 @@ import (
 	"strings"
 
 	"git.warky.dev/wdevs/relspecgo/pkg/models"
+	"git.warky.dev/wdevs/relspecgo/pkg/pgsql"
 )
 
 func (w *Writer) sqlTypeToGraphQL(sqlType string, column *models.Column, table *models.Table, schema *models.Schema) string {
@@ -33,12 +34,11 @@ func (w *Writer) sqlTypeToGraphQL(sqlType string, column *models.Column, table *
 	}
 
 	// Standard type mappings
-	baseType := strings.Split(sqlType, "(")[0] // Remove length/precision
-	baseType = strings.TrimSpace(baseType)
+	baseType := pgsql.CanonicalizeBaseType(pgsql.ExtractBaseTypeLower(sqlType))
 
 	// Handle array types
-	if strings.HasSuffix(baseType, "[]") {
-		elemType := strings.TrimSuffix(baseType, "[]")
+	if pgsql.IsArrayType(sqlType) {
+		elemType := pgsql.CanonicalizeBaseType(pgsql.ExtractBaseTypeLower(pgsql.ElementType(sqlType)))
 		gqlType := w.mapBaseTypeToGraphQL(elemType)
 		return "[" + gqlType + "]"
 	}
@@ -108,8 +108,7 @@ func (w *Writer) sqlTypeToCustomScalar(sqlType string) string {
 		"date":                     "Date",
 	}
 
-	baseType := strings.Split(sqlType, "(")[0]
-	baseType = strings.TrimSpace(baseType)
+	baseType := pgsql.CanonicalizeBaseType(pgsql.ExtractBaseTypeLower(sqlType))
 
 	if scalar, ok := scalarMap[baseType]; ok {
 		return scalar
@@ -132,8 +131,7 @@ func (w *Writer) isIntegerType(sqlType string) bool {
 		"smallserial": true,
 	}
 
-	baseType := strings.Split(sqlType, "(")[0]
-	baseType = strings.TrimSpace(baseType)
+	baseType := pgsql.CanonicalizeBaseType(pgsql.ExtractBaseTypeLower(sqlType))
 
 	return intTypes[baseType]
 }