Add: German Translation (#2725)

# Description

Please provide a summary of the changes, including relevant motivation
and context.

Closes #(issue_number)

## Checklist

- [x] I have read the [Contribution
Guidelines](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/CONTRIBUTING.md)
- [x] I have performed a self-review of my own code
- [ ] I have attached images of the change if it is UI based
- [ ] I have commented my code, particularly in hard-to-understand areas
- [ ] If my code has heavily changed functionality I have updated
relevant docs on [Stirling-PDFs doc
repo](https://github.com/Stirling-Tools/Stirling-Tools.github.io/blob/main/docs/)
- [x] My changes generate no new warnings
- [ ] I have read the section [Add New Translation
Tags](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/HowToAddNewLanguage.md#add-new-translation-tags)
(for new translation tags only)

scripts/ignore_translation.toml

@@ -56,6 +56,7 @@ ignore = [
     'validateSignature.cert.version',
     'validateSignature.status',
     'watermark.type.1',
+    'redact.zoom',
 ]
 
 [el_GR]

src/main/resources/messages_de_DE.properties

@@ -862,7 +862,7 @@ sign.first=Erste Seite
 sign.last=Letzte Seite
 sign.next=Nächste Seite
 sign.previous=Vorherige Seite
-sign.maintainRatio=Toggle maintain aspect ratio
+sign.maintainRatio=Seitenverhältnis beibehalten ein-/ausschalten
 
 
 #repair
@@ -1320,8 +1320,8 @@ splitByChapters.submit=PDF teilen
 fileChooser.click=Klicken
 fileChooser.or=oder
 fileChooser.dragAndDrop=Drag & Drop
-fileChooser.dragAndDropPDF=Drag & Drop PDF file
-fileChooser.dragAndDropImage=Drag & Drop Image file
+fileChooser.dragAndDropPDF=Drag & Drop PDF-Datei
+fileChooser.dragAndDropImage=Drag & Drop Bilddatei
 fileChooser.hoveredDragAndDrop=Datei(en) hierhin Ziehen & Fallenlassen
 
 #release notes