feat(admin-ui): enhance dark mode support across UI components

- Updated various components in the llm-router to include dark mode styles, ensuring better visibility and aesthetics in dark theme.
- Added tests for API URL helpers to validate sign-in URL construction and redirection logic.
- Improved the sign-in flow to handle trusted redirects for standalone admin origins.
- Enhanced CSS styles for dark mode, including adjustments to backgrounds, borders, and text colors for better contrast and readability.
- Refactored input components to maintain consistent styling in both light and dark modes.

packages/ui/src/components/form/field/field-input.vue

@@ -85,6 +85,7 @@ const modelValue = defineModel<T>({ required: false })
           'text-disabled:neutral-400 dark:text-disabled:neutral-600',
           'cursor-disabled:not-allowed',
           'w-full rounded-lg px-2 py-1 text-sm outline-none',
+          'text-neutral-900 dark:text-neutral-100 placeholder:text-neutral-400 dark:placeholder:text-neutral-500',
           'shadow-sm',
           'bg-neutral-50 dark:bg-neutral-950 focus:bg-neutral-50 dark:focus:bg-neutral-900',
         ]"

packages/ui/src/components/form/input/input.vue

@@ -40,6 +40,7 @@ const variantClasses: Record<InputVariant, Record<InputTheme, {
       default: [
         'w-full rounded-lg px-2 py-1 text-nowrap text-sm outline-none',
         'bg-neutral-50 dark:bg-neutral-950 focus:bg-neutral-50 dark:focus:bg-neutral-900',
+        'text-neutral-900 dark:text-neutral-100 placeholder:text-neutral-400 dark:placeholder:text-neutral-500',
         'focus:border-primary-300 dark:focus:border-primary-400/50 border-2 border-solid border-neutral-100 dark:border-neutral-900',
         'text-disabled:neutral-400 dark:text-disabled:neutral-600',
         'shadow-sm',
@@ -51,6 +52,7 @@ const variantClasses: Record<InputVariant, Record<InputTheme, {
       default: [
         'w-full rounded-lg px-2 py-1 text-nowrap text-sm outline-none',
         'bg-neutral-50 dark:bg-neutral-950 focus:bg-neutral-50 dark:focus:bg-neutral-900',
+        'text-neutral-900 dark:text-neutral-100 placeholder:text-neutral-400 dark:placeholder:text-neutral-500',
         'focus:border-primary-300 dark:focus:border-primary-400/50 border-2 border-solid border-neutral-100 dark:border-neutral-900',
         'text-disabled:neutral-400 dark:text-disabled:neutral-600',
         'shadow-sm',
@@ -62,6 +64,7 @@ const variantClasses: Record<InputVariant, Record<InputTheme, {
       default: [
         'w-full rounded-lg px-2 py-1 text-nowrap text-sm outline-none',
         'bg-neutral-100 dark:bg-neutral-800 focus:bg-neutral-50 dark:focus:bg-neutral-950',
+        'text-neutral-900 dark:text-neutral-100 placeholder:text-neutral-400 dark:placeholder:text-neutral-500',
         'focus:border-primary-500/30 dark:focus:border-primary-400/50 border-2 border-solid border-neutral-500/5 dark:border-neutral-700/40',
         'text-disabled:neutral-400 dark:text-disabled:neutral-600',
       ],

packages/ui/src/components/form/textarea/textarea.vue

@@ -13,6 +13,7 @@ const modelValue = defineModel<string>({ default: '' })
       'text-disabled:neutral-400 dark:text-disabled:neutral-600',
       'cursor-disabled:not-allowed',
       'w-full rounded-lg px-2 py-1 text-nowrap text-sm outline-none',
+      'text-neutral-900 dark:text-neutral-100 placeholder:text-neutral-400 dark:placeholder:text-neutral-500',
       'shadow-sm',
       'bg-neutral-50 dark:bg-neutral-950 focus:bg-neutral-50 dark:focus:bg-neutral-900',
     ]"

packages/ui/src/components/misc/button.vue

@@ -154,7 +154,7 @@ const baseClasses = computed(() => {
   const theme = variant[props.theme] || variant.default
 
   return [
-    'font-medium outline-none',
+    'font-medium outline-none whitespace-nowrap',
     'transition-all duration-200 ease-in-out',
     'disabled:cursor-not-allowed disabled:opacity-50',
     'backdrop-blur-md',