refactor: group AlterTypeStmt and objtype conditions in RangeVar for better readability

- Group (!context.parentNodeTypes.includes('AlterTypeStmt') && context.objtype !== 'OBJECT_TYPE') conditions
- Improves code semantics by making it clear both conditions relate to preventing ONLY keyword for ALTER TYPE operations
- Remove ternary operator from RenameStmt to maintain universal spawn() flow
- All 279 test suites passing

Co-Authored-By: Dan Lynch <[email protected]>

Author: devin-ai-integration[bot]