Add glass UI with backdrop blur and fix primary button colors

Apply glassmorphism to sidebar, cards, tables, modals, dropdowns,
and dialogs with semi-transparent backgrounds, backdrop-blur, and
white/15 borders. Add subtle gradient body background for the blur
to work against. Add dedicated btn-primary color tokens so primary
buttons stay bold in dark mode instead of using the brightened text
palette. Use shadow-sm to avoid heavy halos in light mode.

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

resources/scripts/components/base/BaseModal.vue

@@ -51,8 +51,8 @@
             <div
               :class="`inline-block
               align-middle
-              bg-surface
-              rounded-lg
+              bg-surface/80 backdrop-blur-2xl
+              rounded-xl border border-white/15
               text-left
               overflow-hidden
               relative