feat(i18n): add German translations

[Ludy87]

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.

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Checklist

General

• I have read the Contribution Guidelines
• I have read the Stirling-PDF Developer Guide (if applicable)
• I have read the How to add new languages to Stirling-PDF (if applicable)
• I have performed a self-review of my own code
• My changes generate no new warnings

Documentation

• I have updated relevant docs on Stirling-PDF's doc repo (if functionality has heavily changed)
• I have read the section 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 for more details.

[stirlingbot]

🚀 Translation Verification Summary

🔄 Reference Branch: main-branch-messages_en_GB.properties

📃 File Check: messages_de_DE.properties

1. Test Status: ✅ Passed
2. Test Status: ✅ Passed
3. Test Status: ✅ Passed

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✅ Overall Check Status: Success

Thanks @Ludy87 for your help in keeping the translations up to date.

[Copilot]

Pull Request Overview

This PR improves German translations for the Stirling PDF application by completing an incomplete translation string and enabling translation for a previously ignored key.

• Removed scannerEffect.quality.medium from the translation ignore list
• Fixed incomplete urgent update notification text in German
• Updated analytics labels to use German translations

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
scripts/ignore_translation.toml	Removed scannerEffect.quality.medium from ignore list to enable proper translation
app/core/src/main/resources/messages_de_DE.properties	Fixed incomplete urgent update text and updated analytics cookie labels with German translations

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