fix(FN-4359): use theme-safe column badge tint in ListView

Internal docs task received workflow revision feedback requiring an in-place UI fix.\nNo changeset added per AGENTS.md 'Finalizing Changes' policy (no published package behavior release intent).

Fusion-Task-Id: FN-4359
Fusion-Task-Lineage: c26f1959-0b99-4b4c-b7d5-46170ae2bacd

packages/dashboard/app/components/ListView.tsx

@@ -1584,7 +1584,7 @@ export function ListView({
                                     <span
                                       className="list-column-badge"
                                       style={{
-                                        background: `${COLUMN_COLOR_MAP[task.column]}20`,
+                                        background: `color-mix(in srgb, ${COLUMN_COLOR_MAP[task.column]} 12%, transparent)`,
                                         color: COLUMN_COLOR_MAP[task.column],
                                       }}
                                     >