style(admin): switch feedback-category badges to dracula tokens

P17. The category badges (BUG / FEATURE_REQUEST / QUESTION / OTHER)
were using raw Tailwind palette values (bg-red-500/15 text-red-400 etc.)
which clash with the rest of the app's Dracula tokens. Switch to the
dracula-red / dracula-purple / dracula-cyan equivalents so the inbox
matches the site theme — and dark/light mode parity is consistent
with every other status badge in the admin grid.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/components/admin/feedback-inbox-section.tsx

@@ -206,15 +206,18 @@ function FeedbackCategoryBadge({
   > = {
     BUG: {
       label: t("admin.feedback.categoryBug"),
-      className: "bg-red-500/15 text-red-400 border-red-500/30",
+      className:
+        "bg-dracula-red/15 text-dracula-red border-dracula-red/30",
     },
     FEATURE_REQUEST: {
       label: t("admin.feedback.categoryFeature"),
-      className: "bg-purple-500/15 text-purple-400 border-purple-500/30",
+      className:
+        "bg-dracula-purple/15 text-dracula-purple border-dracula-purple/30",
     },
     QUESTION: {
       label: t("admin.feedback.categoryQuestion"),
-      className: "bg-blue-500/15 text-blue-400 border-blue-500/30",
+      className:
+        "bg-dracula-cyan/15 text-dracula-cyan border-dracula-cyan/30",
     },
     OTHER: {
       label: t("admin.feedback.categoryOther"),