fix: address a11y code review findings

Bugs fixed:
- Space key was hijacked in tag input when a suggestion was
  highlighted, preventing users from typing spaces. Removed
  Space as a selection key (Enter is sufficient per combobox
  pattern).
- ArrowUp was clamped to index 0, making it impossible to
  deselect all suggestions and return to free typing. Now
  allows arrowing back to -1 which clears aria-activedescendant.

Cleanup:
- Remove dead inline onkeydown handlers from tag suggestion
  <li> elements (tabindex="-1" means they never receive focus,
  so the handlers never fire; the global keydown listener in
  app.js handles keyboard navigation).
- Add outline to aria-selected="true" state for visual parity
  with hover (keyboard users now see the same indicator).
- Announce "Ingen forslag" in live region when suggestions are
  empty (screen readers previously got silence).
- Add responsive table wrapper to admin tags and admin requests
  tables (was only on admin users).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

web/static/css/style.css

@@ -164,6 +164,8 @@
 
 .tag-suggestion[aria-selected="true"] {
     background: var(--pico-primary-focus);
+    outline: 2px solid var(--pico-primary);
+    outline-offset: -2px;
 }
 
 /* Fave detail actions */

web/static/js/app.js

@@ -48,7 +48,7 @@
             if (status) {
                 status.textContent = count > 0
                     ? count + " forslag tilgjengelig"
-                    : "";
+                    : "Ingen forslag";
             }
 
             // Reset active descendant tracking.
@@ -88,21 +88,19 @@
             break;
         case "ArrowUp":
             event.preventDefault();
-            activeIndex = Math.max(activeIndex - 1, 0);
-            setActiveDescendant(items);
+            // Allow arrowing back to -1 to deselect all options.
+            activeIndex = Math.max(activeIndex - 1, -1);
+            if (activeIndex === -1) {
+                clearActiveDescendant();
+                clearAriaSelected(items);
+            } else {
+                setActiveDescendant(items);
+            }
             break;
         case "Enter":
             if (activeIndex >= 0 && activeIndex < items.length) {
                 event.preventDefault();
-                var tagName = items[activeIndex].textContent.trim();
-                addTag(null, tagName);
-            }
-            break;
-        case " ":
-            if (activeIndex >= 0 && activeIndex < items.length) {
-                event.preventDefault();
-                var tagName2 = items[activeIndex].textContent.trim();
-                addTag(null, tagName2);
+                addTag(null, items[activeIndex].textContent.trim());
             }
             break;
         case "Escape":
@@ -133,6 +131,12 @@
         }
     }
 
+    function clearAriaSelected(items) {
+        for (var i = 0; i < items.length; i++) {
+            items[i].setAttribute("aria-selected", "false");
+        }
+    }
+
     function closeSuggestions() {
         var listbox = document.getElementById("tag-suggestions");
         if (listbox) {