Feat: Add German language support for agent template and various UI elements (#12830)

### What problem does this PR solve?

This PR updates and extends the german language support in the frontend.
Additionally two more elements are handled dynamically now. The
interactive Agent is also titled and described in german now.

### Type of change

- [x] New Feature (non-breaking change which adds functionality)

Co-authored-by: Jakob <16180662+hauberj@users.noreply.github.com>

agent/templates/user_interaction.json

@@ -2,10 +2,12 @@
     "id": 27,
     "title": {
         "en": "Interactive Agent",
+        "de": "Interaktiver Agent",
         "zh": "可交互的 Agent"
     },
     "description": {
         "en": "During the Agent’s execution, users can actively intervene and interact with the Agent to adjust or guide its output, ensuring the final result aligns with their intentions.",
+        "de": "Wahrend der Ausführung des Agenten können Benutzer aktiv eingreifen und mit dem Agenten interagieren, um dessen Ausgabe zu steuern, sodass das Endergebnis ihren Vorstellungen entspricht.",
         "zh": "在 Agent 的运行过程中，用户可以随时介入，与 Agent 进行交互，以调整或引导生成结果，使最终输出更符合预期。"
     },
     "canvas_type": "Agent",