[omartio]

What does this PR do?

Adds an Add to Exclusions action to the context menu for file and folder scan results.

• Persists excluded paths and removes them from the current result immediately.
• Applies exclusions to manual, smart, and scheduled cleaning scans.
• Preserves and migrates the existing Large & Old Files folder exclusions.
• Lets users manage excluded files and folders in Settings → Cleaning.
• Documents the behavior in the README and localizes the new UI strings.

Type of change

• Bug fix
• New feature
• Performance improvement
• UI/UX enhancement
• Documentation
• Other (describe)

Testing

• Tested on macOS Ventura (13.x)
• Tested on macOS Sonoma (14.x)
• Tested on macOS Sequoia (15.x)
• All 27 macOS unit tests pass on macOS 26.5.2

Ventura hardware or a Ventura VM was not available in the development environment, so that checkbox is intentionally left unchecked. The project continues to target macOS 13.0+.

Screenshots

Not included. The visible change is a single context-menu action plus the existing Cleaning settings list expanded to accept files as well as folders.