fix(web): remove global input:focus-visible override for consistent focus outlines (#19498)

The blanket `input:focus-visible { outline: none !important; }` rule in
app.css suppressed keyboard focus indicators from all native inputs
while @immich/ui buttons kept their own focus-visible outline. This
produced an inconsistent and inaccessible experience on admin/settings
pages where raw inputs and UI buttons are mixed.

Removing the global override restores the browser default focus ring
on native inputs. Inputs using the `immich-form-input` utility already
have their own ring styling, so this change is safe for the existing
design system.

web/src/app.css

@@ -153,10 +153,12 @@
     background-color: black;
   }
 
-  input:focus-visible {
+  /* Removed global input:focus-visible override to ensure consistent,
+     accessible focus outlines across all pages (fixes #19498). */
+  /* input:focus-visible {
     outline-offset: 0px !important;
     outline: none !important;
-  }
+  } */
 
   .text-white-shadow {
     text-shadow: 0 1px 2px rgba(0, 0, 0, 0.8);