Fix PoolBar links using wrong query params for task instances filtering (apache#64182)

The PoolBar component links to the task instances page using
SearchParamsKeys.STATE ('state') and SearchParamsKeys.POOL ('pool'),
but the TaskInstances page reads filters from SearchParamsKeys.TASK_STATE
('task_state') and SearchParamsKeys.POOL_NAME_PATTERN ('pool_name_pattern').

This mismatch causes clicking a pool slot segment (running, queued, etc.)
to navigate to the task instances page without any filters being applied,
showing all task instances instead of those filtered by the clicked state
and pool.

Fix by using the correct search parameter keys (TASK_STATE and
POOL_NAME_PATTERN) and slot.slotType instead of slot.color for the
state filter value.

Author: Karthikeya1500

airflow-core/src/airflow/ui/src/components/PoolBar.tsx

@@ -106,7 +106,7 @@ export const PoolBar = ({
           return slot.color !== "success" && "name" in pool ? (
             <Link asChild flex={flexValue} key={slot.key}>
               <RouterLink
-                to={`/task_instances?${SearchParamsKeys.STATE}=${slot.color}&${SearchParamsKeys.POOL}=${pool.name}`}
+                to={`/task_instances?${SearchParamsKeys.TASK_STATE}=${slot.slotType}&${SearchParamsKeys.POOL_NAME_PATTERN}=${pool.name}`}
               >
                 {poolContent}
               </RouterLink>