fix: align frontend interfaces with backend DTO field names

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

ui/src/api/queries/admin/database.ts

@@ -6,26 +6,29 @@ export interface DatabaseStatus {
   version: string;
   host: string;
   schema: string;
+  timescaleDb: boolean;
 }
 
 export interface PoolStats {
   activeConnections: number;
   idleConnections: number;
-  pendingConnections: number;
-  maxConnections: number;
-  maxWaitMillis: number;
+  pendingThreads: number;
+  maxPoolSize: number;
+  maxWaitMs: number;
 }
 
 export interface TableInfo {
   tableName: string;
-  rowEstimate: number;
+  rowCount: number;
   dataSize: string;
   indexSize: string;
+  dataSizeBytes: number;
+  indexSizeBytes: number;
 }
 
 export interface ActiveQuery {
   pid: number;
-  durationMs: number;
+  durationSeconds: number;
   state: string;
   query: string;
 }
@@ -64,7 +67,7 @@ export function useKillQuery() {
   const qc = useQueryClient();
   return useMutation({
     mutationFn: async (pid: number) => {
-      await adminFetch<void>(`/database/queries/${pid}`, { method: 'DELETE' });
+      await adminFetch<void>(`/database/queries/${pid}/kill`, { method: 'POST' });
     },
     onSuccess: () => qc.invalidateQueries({ queryKey: ['admin', 'database', 'queries'] }),
   });