Establish quality standards

[carstingaxion]

### Repository Standards
- [x] Has nice [README.md](https://github.com/figuren-theater/new-ft-module/blob/main/README.md)
- [x] Add [`.github/workflows/ft-issue-gardening.yml`](https://github.com/figuren-theater/new-ft-module/blob/main/.github/workflows/ft-issue-gardening.yml) file (if not exists)
- [x] Add [`.github/workflows/release-drafter.yml`](https://github.com/figuren-theater/new-ft-module/blob/main/.github/workflows/release-drafter.yml) file
- [x] Add [`.github/workflows/prerelease-changelog.yml`](https://github.com/figuren-theater/new-ft-module/blob/main/.github/workflows/prerelease-changelog.yml) file
- [x] Add [`.editorconfig`](https://github.com/figuren-theater/new-ft-module/blob/main/.editorconfig) file
- [x] Add [`.phpcs.xml`](https://github.com/figuren-theater/new-ft-module/blob/main/.phpcs.xml) file
- [x] Check that `.phpcs.xml` file is not present in `.gitignore`
- [x] Add [`CHANGELOG.md`](https://github.com/figuren-theater/new-ft-module/blob/main/CHANGELOG.md) file with an *Unreleased-Heading*
- [x] Add [`phpstan.neon`](https://github.com/figuren-theater/new-ft-module/blob/main/phpstan.neon) file
- [x] Run `composer require --dev figuren-theater/code-quality`
- [x] Run `composer normalize`
- [x] Run `vendor/bin/phpstan analyze .` without errors
- [x] Run `vendor/bin/phpcs .` without errors
- [x] Fix all errors ;)
- [x] commit, PR & merge all (additional) changes !
- [x] Has branch protection enabled ?
- [x] Add [`.github/workflows/build-test-measure.yml`](https://github.com/figuren-theater/new-ft-module/blob/main/.github/workflows/build-test-measure.yml) file
- [x] Enable repo for required **Build, test & measure** status checks via [Repo Settings](/settings/actions)
- [x] Add **Build, test & measure** badge to the [code-quality](https://github.com/figuren-theater/code-quality) README
- [x] Submit repo to [packagist.org](https://packagist.org/packages/figuren-theater/)
- [x] Remove explicit `repositories` entry from [ft-platform](https://github.com/figuren-theater/ft-platform)s `composer.json`
- [x] Remove explicit `repositories` entry from [ft-site-editing](https://github.com/figuren-theater/ft-site-editing)s `composer.json`
- [x] Update `README.md` and fix **LICENSE-Link**, to see all workflows running
- [x] Publish the new drafted Release as Prerelease to trigger auto-updating versions in CHANGELOG.md and plugin.php

### Plugin Standards
- [x] Plugin is translation ready
- [x] Has `de_DE` & `de_DE_formal` translation(s) available (if present in the UI)