Add query cancellation controls (#41)

Co-authored-by: SuLe <sule@SuLedeMacBook-Air.local>
Co-authored-by: skyler <77960507+t8y2@users.noreply.github.com>

src/lib/queryExecutionState.ts

@@ -0,0 +1,13 @@
+export interface QueryExecutionStateLike {
+  isExecuting: boolean;
+  isCancelling?: boolean;
+  executionId?: string;
+}
+
+export function canCancelQueryExecution(state: QueryExecutionStateLike): boolean {
+  return state.isExecuting && !!state.executionId && !state.isCancelling;
+}
+
+export function queryExecutionLabelKey(state: Pick<QueryExecutionStateLike, "isCancelling">): "common.loading" | "common.stopping" {
+  return state.isCancelling ? "common.stopping" : "common.loading";
+}