fix: writer/reader correctness and determinism issues

- merge: cloneTable keeps relationships; skip-tables applies to new schemas
- diff: detect schema description/owner changes
- prisma: reader no longer turns relation fields into columns, enum
  detection via declared names; writer type mapping is ordered
- typeorm writer: keep explicit SQL types that cannot be inferred
- drizzle: enum columns call the enum constant; reader resolves them
- mysql/mssql/sqlite writers: honour OutputPath, deterministic column
  and constraint order; mssql live execute covers full schema
- template: ToYAML recovers from panics; Merge nil-pointer loop
- regenerate drizzle fixtures

pkg/diff/diff.go

@@ -71,6 +71,13 @@ func compareSchemas(source, target []*models.Schema) *SchemaDiff {
 	return diff
 }
 
+func (c *SchemaChange) addChange(field string, source, target any) {
+	if c.Changes == nil {
+		c.Changes = make(map[string]any)
+	}
+	c.Changes[field] = map[string]any{"source": source, "target": target}
+}
+
 func compareSchemaDetails(source, target *models.Schema) *SchemaChange {
 	change := &SchemaChange{
 		Name: source.Name,
@@ -78,6 +85,16 @@ func compareSchemaDetails(source, target *models.Schema) *SchemaChange {
 
 	hasChanges := false
 
+	// Compare schema attributes
+	if source.Description != target.Description {
+		change.addChange("description", source.Description, target.Description)
+		hasChanges = true
+	}
+	if source.Owner != target.Owner {
+		change.addChange("owner", source.Owner, target.Owner)
+		hasChanges = true
+	}
+
 	// Compare tables
 	tableDiff := compareTables(source.Tables, target.Tables)
 	if !isEmpty(tableDiff) {