#3429 refactor: Enable Ruff `FURB` rules Pull request opened by edgarrmondragon ## Summary by Sourcery Enable Ruff FURB rules and update codebase to satisfy new linting checks. Enhancements: • Refine use of abstract base classes by inheriting directly from abc.ABC instead of specifying ABCMeta as metaclass. • Adopt more concise and expressive standard library helpers (e.g., operator.itemgetter, truthiness of lists) and modern file I/O helpers for configuration writing. • Change catalog and selection mapping classes to use UserDict-based wrappers where appropriate for clearer semantics. Build: • Update Ruff configuration to enable FURB (refurb) rule set. Tests: • Adjust typing conformance tests to align with updated numeric example values. meltano/sdk