fix(ui): resolve light-theme low-contrast semantic text app-wide (#1909)

The app was built dark-first, so hundreds of hardcoded Tailwind semantic
text/icon utilities at light shades (text-amber-400, text-blue-300, ...) had
no dark: variant. With darkMode:'class' they applied in light theme too,
producing washed-out text on pale tints and white cards — including the three
reported spots (AMS Drying banner, Archives no-3MF warning, debug-logging
banner). Give each a theme-aware pair: a darker readable shade in light theme
with the original pinned to dark:, so dark theme is unchanged. ~100 files.

The bambu-* CSS-variable palette (self-correcting) and the dark-only SpoolBuddy
kiosk are left untouched. Plain text-white is already theme-aware via the
existing index.css .text-white override, so it needed no changes.

frontend/src/components/BatchProjectModal.tsx

@@ -129,7 +129,7 @@ export function BatchProjectModal({ selectedIds, onClose }: BatchProjectModalPro
                   className="w-full flex items-center gap-3 p-3 rounded-lg bg-bambu-dark hover:bg-bambu-dark-tertiary border border-bambu-dark-tertiary transition-colors text-left disabled:opacity-50"
                 >
                   <div className="w-8 h-8 rounded-full bg-red-500/20 flex items-center justify-center shrink-0">
-                    <XCircle className="w-4 h-4 text-red-400" />
+                    <XCircle className="w-4 h-4 text-red-600 dark:text-red-400" />
                   </div>
                   <div className="min-w-0 flex-1">
                     <p className="text-white font-medium">Remove from project</p>