feat(pgsql): support vector and PostGIS indexes with extensions

* Add handling for pgvector and PostGIS extensions in migration scripts
* Implement operator class and storage parameters for vector indexes
* Update tests to validate new index behaviors and extension creation

pkg/readers/pgsql/reader.go

@@ -88,6 +88,18 @@ func (r *Reader) ReadDatabase() (*models.Database, error) {
 		}
 		schema.Sequences = sequences
 
+		// Query extensions installed into this schema
+		extensions, err := r.queryExtensions(schema.Name)
+		if err != nil {
+			return nil, fmt.Errorf("failed to query extensions for schema %s: %w", schema.Name, err)
+		}
+		if len(extensions) > 0 {
+			if schema.Metadata == nil {
+				schema.Metadata = make(map[string]any)
+			}
+			schema.Metadata["extensions"] = extensions
+		}
+
 		// Query columns for tables and views
 		columnsMap, err := r.queryColumns(schema.Name)
 		if err != nil {
@@ -278,11 +290,6 @@ func (r *Reader) mapDataType(pgType, udtName, formattedType string, hasNextval b
 		}
 	}
 
-	// information_schema reports arrays generically as "ARRAY" with udt_name like "_text".
-	if strings.EqualFold(pgType, "ARRAY") && strings.HasPrefix(udtName, "_") && len(udtName) > 1 {
-		return udtName[1:] + "[]"
-	}
-
 	// Use the database-formatted type when available. For known built-in types, strip
 	// embedded dimensions (they are stored in column.Length/Precision/Scale separately).
 	// For unknown/custom types, keep the full formatted string (e.g. vector(1536)).
@@ -303,6 +310,13 @@ func (r *Reader) mapDataType(pgType, udtName, formattedType string, hasNextval b
 		return formattedType
 	}
 
+	// information_schema reports arrays generically as "ARRAY" with udt_name like "_text".
+	// Only reached when the catalog-formatted type is unavailable, which is the one case
+	// where the element modifier (e.g. geometry(Point,4326)[]) cannot be recovered.
+	if strings.EqualFold(pgType, "ARRAY") && strings.HasPrefix(udtName, "_") && len(udtName) > 1 {
+		return udtName[1:] + "[]"
+	}
+
 	// Fall back to normalizing the information_schema type name directly.
 	canonical := pgsql.NormalizePGType(normalizedPGType)
 	if pgsql.IsKnownPGBaseType(canonical) {