fix: Dashboard Card-Dropdown nicht mehr abgeschnitten

- CSS: position: fixed statt absolute, z-index: 1000, box-shadow
- JS: Position dynamisch berechnet (getBoundingClientRect) beim Öffnen
- Viewport-Overflow-Korrektur falls Dropdown zu weit rechts/links

wwwroot/css/dashboard.css

@@ -211,10 +211,7 @@
 }
 
 .card-menu-dropdown {
-  margin-top: var(--badge-spacing);
-  position: absolute;
-  top: 100%;
-  right: 0;
+  position: fixed;
   background: var(--f3-bg);
   border: var(--border-width) solid var(--f3-border);
   border-radius: var(--border-radius);
@@ -223,6 +220,8 @@
   flex-direction: column;
   overflow: hidden;
   padding-block: var(--badge-spacing);
+  z-index: 1000;
+  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
 }
 
 .card-menu-dropdown[hidden] {

wwwroot/js/pages/dashboard.js

@@ -78,7 +78,21 @@ registerPage('dashboard', {
       menuTrigger.addEventListener('click', (e) => {
         e.stopPropagation();
         closeAllCardMenus();
+        // Position fixed dropdown relative to trigger
+        const rect = menuTrigger.getBoundingClientRect();
+        menuDropdown.style.top = `${rect.bottom + 4}px`;
+        menuDropdown.style.left = `${rect.right - menuDropdown.offsetWidth}px`;
         menuDropdown.hidden = !menuDropdown.hidden;
+        // Adjust if off-screen right
+        if (!menuDropdown.hidden) {
+          const dropRect = menuDropdown.getBoundingClientRect();
+          if (dropRect.right > window.innerWidth) {
+            menuDropdown.style.left = `${window.innerWidth - dropRect.width - 8}px`;
+          }
+          if (dropRect.left < 0) {
+            menuDropdown.style.left = '8px';
+          }
+        }
       });
       chatBtn.addEventListener('click', (e) => {
         e.stopPropagation();
@@ -209,7 +223,21 @@ registerPage('dashboard', {
       menuTrigger.addEventListener('click', (e) => {
         e.stopPropagation();
         closeAllCardMenus();
+        // Position fixed dropdown relative to trigger
+        const rect = menuTrigger.getBoundingClientRect();
+        menuDropdown.style.top = `${rect.bottom + 4}px`;
+        menuDropdown.style.left = `${rect.right - menuDropdown.offsetWidth}px`;
         menuDropdown.hidden = !menuDropdown.hidden;
+        // Adjust if off-screen right
+        if (!menuDropdown.hidden) {
+          const dropRect = menuDropdown.getBoundingClientRect();
+          if (dropRect.right > window.innerWidth) {
+            menuDropdown.style.left = `${window.innerWidth - dropRect.width - 8}px`;
+          }
+          if (dropRect.left < 0) {
+            menuDropdown.style.left = '8px';
+          }
+        }
       });
       menuDropdown.querySelector('[data-action="files"]').addEventListener('click', (e) => {
         e.stopPropagation();