GHSA-FC2G-4W5P-6WHM virtualenv: Seeded files retain permissions from an older cache

Summary The app-data copy seeder uses shutil.copy, which preserves cached file modes independently of the current umask. A cache populated under permissive permissions can therefore produce files with wider access in later environments. Anthropic's OSS Scanner reported this as ANT-2026-487MH6OW i...