style(visual-fidelity): pages-admin — batches B,C,F

- B: token-equivalent rgba → color-mix(srgb, var(--ember|green|candle) X%, transparent) so colors track dark mode
- C: drop stale var(--green, #...) fallbacks (canonical token now defined in main.css)
- F: inline circle badge → <CircleBadge/> in admin/index, members/[id], members/index

app/pages/admin/series-management.vue

@@ -850,7 +850,7 @@ const exportSeriesData = () => {
   font-size: 11px;
   font-weight: 600;
   color: var(--c-founder);
-  border: 1px dashed rgba(138, 68, 32, 0.4);
+  border: 1px dashed color-mix(in srgb, var(--ember) 40%, transparent);
   border-radius: 50%;
   flex-shrink: 0;
 }
@@ -931,12 +931,12 @@ const exportSeriesData = () => {
 
 .status-active {
   color: var(--green);
-  border-color: rgba(74, 106, 56, 0.3);
+  border-color: color-mix(in srgb, var(--green) 30%, transparent);
 }
 
 .status-upcoming {
   color: var(--candle);
-  border-color: rgba(122, 90, 16, 0.3);
+  border-color: color-mix(in srgb, var(--candle) 30%, transparent);
 }
 
 .status-completed {
@@ -946,7 +946,7 @@ const exportSeriesData = () => {
 
 .status-ongoing {
   color: var(--green);
-  border-color: rgba(74, 106, 56, 0.3);
+  border-color: color-mix(in srgb, var(--green) 30%, transparent);
 }
 
 /* ---- LINK BUTTONS ---- */