fix: scope correlation-chain query to the exchange's own env

Correlated exchanges always share the env of the one being viewed —
using the globally-selected env from the picker was wrong if the user
switched envs after opening a detail view (or arrived via permalink).

Thread `environment` through:
- `ExecutionStore.ExecutionRecord` gains `environment` field; the
  ClickHouse `executions` table already stores this, just not read back.
- `ClickHouseExecutionStore.findById` SELECT adds the column; mapper
  populates it.
- `ExecutionDetail` gains `environment`; `DetailService` passes through.
- `IngestionService.toExecutionRecord` passes null — this legacy PG
  ingestion path isn't active when ClickHouse is enabled, and the
  read-side is what drives the correlation UI.
- UI `ExchangeHeader` reads `detail.environment ?? storeEnv` and
  extends the TS type locally (schema.d.ts catches up on next regen).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

ui/src/pages/Exchanges/ExchangeHeader.tsx

@@ -33,7 +33,11 @@ function statusVariant(s: string): StatusVariant {
 export function ExchangeHeader({ detail, onCorrelatedSelect, onClearSelection }: ExchangeHeaderProps) {
   const navigate = useNavigate();
   const { timeRange } = useGlobalFilters();
-  const environment = useEnvironmentStore((s) => s.environment);
+  const storeEnv = useEnvironmentStore((s) => s.environment);
+  // Prefer the exchange's own env over the selected env — correlated exchanges
+  // always live in the same env as the one being viewed, and the user may have
+  // switched env-picker after opening this detail.
+  const environment = detail.environment ?? storeEnv;
   const { data: chainResult } = useCorrelationChain(detail.correlationId ?? null, environment);
   const chain = chainResult?.data;
   const showChain = chain && chain.length > 1;