feat(i18n): add German translations (#4796)

# Description of Changes

This pull request makes minor improvements to the German localization
and translation management. The changes primarily update UI strings for
clarity and consistency and adjust the translation ignore list.

Localization improvements:

* Updated urgent update notification and related UI strings in
`messages_de_DE.properties` for better clarity and consistency.
* Improved analytics labels and translated "Scarf Pixel" to
"Schal-Pixel" in `messages_de_DE.properties`.

Translation management:

* Removed `scannerEffect.quality.medium` from the translation ignore
list in `ignore_translation.toml`.

---

## Checklist

### General

- [x] I have read the [Contribution
Guidelines](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/CONTRIBUTING.md)
- [x] I have read the [Stirling-PDF Developer
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/DeveloperGuide.md)
(if applicable)
- [ ] I have read the [How to add new languages to
Stirling-PDF](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/HowToAddNewLanguage.md)
(if applicable)
- [x] I have performed a self-review of my own code
- [x] My changes generate no new warnings

### Documentation

- [ ] I have updated relevant docs on [Stirling-PDF's doc
repo](https://github.com/Stirling-Tools/Stirling-Tools.github.io/blob/main/docs/)
(if functionality has heavily changed)
- [ ] I have read the section [Add New Translation
Tags](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/HowToAddNewLanguage.md#add-new-translation-tags)
(for new translation tags only)

### UI Changes (if applicable)

- [ ] Screenshots or videos demonstrating the UI changes are attached
(e.g., as comments or direct attachments in the PR)

### Testing (if applicable)

- [ ] I have tested my changes locally. Refer to the [Testing
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/DeveloperGuide.md#6-testing)
for more details.

app/core/src/main/resources/messages_de_DE.properties

@@ -372,7 +372,7 @@ settings.update=Update verfügbar
 settings.updateAvailable={0} ist die aktuelle installierte Version. Eine neue Version ({1}) ist verfügbar.
 
 # Update modal and notification strings
-update.urgentUpdateAvailable=🚨 U
+update.urgentUpdateAvailable=🚨 Update verfügbar
 update.updateAvailable=Update verfügbar
 update.modalTitle=Update verfügbar
 update.current=Aktuell
@@ -1941,8 +1941,8 @@ cookieBanner.preferencesModal.necessary.title.2=Immer aktiviert
 cookieBanner.preferencesModal.necessary.description=Diese Cookies sind für das ordnungsgemäße Funktionieren der Website unerlässlich. Sie ermöglichen grundlegende Funktionen wie das Festlegen Ihrer Datenschutzeinstellungen, das Anmelden und das Ausfüllen von Formularen. Daher können sie nicht deaktiviert werden.
 cookieBanner.preferencesModal.analytics.title=Analyse
 cookieBanner.preferencesModal.analytics.description=Diese Cookies helfen uns zu verstehen, wie unsere Tools genutzt werden, damit wir uns darauf konzentrieren können, die Funktionen zu entwickeln, die unserer Community am meisten am Herzen liegen. Seien Sie beruhigt – Stirling PDF kann und wird niemals den Inhalt der Dokumente verfolgen, mit denen Sie arbeiten.
-cookieBanner.preferencesModal.analytics.posthog.label=PostHog Analytics
-cookieBanner.preferencesModal.analytics.scarf.label=Scarf Pixel
+cookieBanner.preferencesModal.analytics.posthog.label=PostHog Analysen
+cookieBanner.preferencesModal.analytics.scarf.label=Schal-Pixel
 
 #scannerEffect
 scannerEffect.title=Scanner-Effect-PDF

scripts/ignore_translation.toml

@@ -240,7 +240,6 @@ ignore = [
     'pipelineOptions.pipelineHeader',
     'pro',
     'redact.zoom',
-    'scannerEffect.quality.medium',
     'sponsor',
     'team.status',
     'text',