Feat: add German translations for all agent templates and optimized line breaks for template titles (#10643)

### What does this PR solve?
German translation for all agent template and optimizing line breaks in
the title for the new translation.

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

web/src/interfaces/database/flow.ts

@@ -52,12 +52,14 @@ export interface IFlowTemplate {
   description: {
     en: string;
     zh: string;
+    de: string;
   };
   dsl: DSL;
   id: string;
   title: {
     en: string;
     zh: string;
+    de: string;
   };
   update_date: string;
   update_time: number;