fix: remove deprecated vitest.workspace.ts to resolve CI test failures

- Remove deprecated vitest.workspace.ts file
- Resolves 'workspace file is deprecated' warning
- Fixes CI test failures caused by deprecated configuration
- Tests now use vite.config.ts configuration exclusively

Resolves CI issue where tests were failing due to deprecated Vitest configuration.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: jonphipps