Tact v1.4.3 release checklist

Improve the changelog for v1.4.3: grammar, wording, polishing
Make sure there are no open issues for the v1.4.3 milestone (except for the current one, of course)
Bump Tact version in:
- package.json file
- CHANGELOG.md: Unreleased -> v1.4.3

Tag the new v1.4.3 release in Git

$ git tag v1.4.3
$ git push origin v1.4.3

Create the new v1.4.3 release on GitHub: https://github.com/tact-lang/tact/releases
Publish the new v1.4.3 release on NPM: @tact-lang/compiler
```
$ git checkout v1.4.3
$ yarn all && npm publish
```
Request or perform the plugins/parsers/tools updates and releases:
- ~~[ ] https://github.com/tact-lang/tact-template~~
- ~~[ ] https://github.com/tact-lang/tact-vscode~~
- ~~[ ] A new release of tact-vscode on the Visual Studio Marketplace~~
- https://github.com/nujan-io/nujan-ide (tracked in: Deploy IDE with Tact v1.4.3 support when it lands on NPM web-ide#80)
~~[ ] TON Dev News Telegram channel announcement~~
~~[ ] Accumulate TON dev chats feedback~~

Provide feedback