feat: standardize input styling with tier system, add depth and admin features

- Define 4 input tier CSS classes (input-standard, input-search, input-embedded, input-danger)
  in globals.css, migrating ~50 inputs across ~28 component files to use them
- Add subtle border and inset shadow to solid input tiers for resting-state visibility
- Fix focus ring clipping in settings panel scroll container
- Fix phantom Tailwind tokens (border-border-primary, placeholder-txt-muted)
- Add admin user management panel, storage management, and account deletion utilities

packages/web/src/components/modals/CreateCategory.tsx

@@ -57,7 +57,7 @@ export function CreateCategoryModal() {
             type="text"
             value={name}
             onChange={(e) => setName(e.target.value)}
-            className="w-full px-3 py-2 bg-surface-input border border-border-soft rounded text-txt-primary outline-none focus:ring-2 focus:ring-accent-primary transition-colors"
+            className="input-standard w-full"
             placeholder="new-category"
             autoFocus
           />