Task/improve language localization for DE (20260729) (#7457)

* Update translations

* Update changelog

CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Changed
 
 - Improved the portfolio summary tab on the home page
+- Improved the language localization for German (`de`)
 - Upgraded `@openrouter/ai-sdk-provider` from version `2.9.1` to `3.0.0`
 - Upgraded `ai` from version `6.0.174` to `7.0.37`
 

apps/client/src/locales/messages.de.xlf

@@ -3287,7 +3287,7 @@
       </trans-unit>
       <trans-unit id="5940479294111486613" datatype="html">
         <source>Invested Capital</source>
-        <target state="new">Invested Capital</target>
+        <target state="translated">Investiertes Kapital</target>
         <context-group purpose="location">
           <context context-type="sourcefile">apps/client/src/app/components/holding-detail-dialog/holding-detail-dialog.html</context>
           <context context-type="linenumber">173</context>
@@ -3667,7 +3667,7 @@
       </trans-unit>
       <trans-unit id="6342682425862972636" datatype="html">
         <source>Investments</source>
-        <target state="new">Investments</target>
+        <target state="translated">Investitionen</target>
         <context-group purpose="location">
           <context context-type="sourcefile">apps/client/src/app/components/portfolio-summary/portfolio-summary.component.html</context>
           <context context-type="linenumber">197</context>