v0.21.1

## What's Changed
* Proper noun caps australia by @hippietrail in https://github.com/Automattic/harper/pull/651
* feat: Flag "discuss about" instead of "discuss" by @hippietrail in https://github.com/Automattic/harper/pull/645
* feat: suggestion to change "sooner than later" by @hippietrail in https://github.com/Automattic/harper/pull/644
* feat: proper noun capitalization for Malaysia by @hippietrail in https://github.com/Automattic/harper/pull/652
* Implements #505 could of, should of, would of -> ... have by @hippietrail in https://github.com/Automattic/harper/pull/647
* Remove Duplicate Spelling Suggestions by @elijah-potter in https://github.com/Automattic/harper/pull/654
* feat(core): condense `further more` by @elijah-potter in https://github.com/Automattic/harper/pull/655
* feat: rename `FullDictionary` -> `MutableDictionary` and add some doc comments by @grantlemons in https://github.com/Automattic/harper/pull/658
* chore: fixes to curated dictionary affixes by @hippietrail in https://github.com/Automattic/harper/pull/650
* build(deps): bump once_cell from 1.20.2 to 1.20.3 by @dependabot in https://github.com/Automattic/harper/pull/634
* feat: add some words to curated dictionary by @hippietrail in https://github.com/Automattic/harper/pull/596
* feat(web): make underlines animate into existence on page load by @elijah-potter in https://github.com/Automattic/harper/pull/664
* Chock full by @hippietrail in https://github.com/Automattic/harper/pull/666
* Several New Linters by @elijah-potter in https://github.com/Automattic/harper/pull/663
* feat: multi-word proper nouns for Canada by @hippietrail in https://github.com/Automattic/harper/pull/657
* fix(core): edge cases in the closed compound noun rule by @elijah-potter in https://github.com/Automattic/harper/pull/670
* docs: add nixpkgs as an installation method by @sumnerevans in https://github.com/Automattic/harper/pull/656

## New Contributors
* @sumnerevans made their first contribution in https://github.com/Automattic/harper/pull/656

**Full Changelog**: https://github.com/Automattic/harper/compare/v0.20.0...v0.21.1