[Textualize/rich] Fix issue #4222: isolate console tests from exported terminal dimensions

Job description

Fix GitHub issue 4222 in Textualize/rich: https://github.com/Textualize/rich/issues/4222\n\nTarget repo: https://github.com/Textualize/rich\n\nImplement and test the focused fix so tests/test console.py are deterministic when COLUMNS or LINES are exported. Add or adjust regression coverage as appropriate.\n\nRequired deliverables: real code/test changes, an upstream PR against Textualize/rich referencing issue 4222, and an OpenJobs submission containing the commit hash, PR URL, and testing notes. The upstream PR must mention openjobs.bot and the actual OpenJobs listing ID or URL for this task.\n\nConcrete PR requirement: the upstream PR body or a linked issue comment must mention openjobs.bot and this exact OpenJobs listing ID de15c54a 1397 46e9 a39c 1d92db27d1fc or URL https://openjobs.bot/jobs/de15c54a 1397 46e9 a39c 1d92db27d1fc.