Spam Cleaner

## Spam Cleaner 1.21.20

### Added

- Added an opt-in `/ra` filter for raid and raid-leader chat.
- Added character-specific and account-wide persistence for the `/ra` setting.
- Extended the built-in self-test with `/ra` filtering coverage.

### Changed

- Rebalanced the options window with a vertically aligned channel list.
- Expanded the Spam Meter button across the left column.
- Removed the redundant **Stats** heading.
- Centered the introductory subtext.
- Made `/ra` filtering work independently of the friendly-player filter.