place-enrichment: the details lookup is a standalone cache fill

The service reads a community place's details before the result cache and
every other place's after it, so the lookup has two call sites of which one
runs. It only fills the details row cache and turns a failure into no
details, so it is tagged @txStandalone and the enrich baseline drops to the
four writes it holds without it.

server/scripts/tx-writes-baseline.json

@@ -57,7 +57,7 @@
   "src/nest/notifications/transports/web-push.service.ts#WebPushService.settle": 2,
   "src/nest/oidc/oidc.controller.ts#OidcController.callback": 2,
   "src/nest/place-enrichment/place-enrichment.service.ts#PlaceEnrichmentService.collectPhotos": 5,
-  "src/nest/place-enrichment/place-enrichment.service.ts#PlaceEnrichmentService.enrich": 5,
+  "src/nest/place-enrichment/place-enrichment.service.ts#PlaceEnrichmentService.enrich": 4,
   "src/nest/place-enrichment/place-enrichment.service.ts#PlaceEnrichmentService.readCache": 2,
   "src/nest/place-enrichment/place-enrichment.service.ts#PlaceEnrichmentService.storeCandidate": 2,
   "src/nest/place-photos/place-photo-cache.job.ts#PlacePhotoCacheJob.onApplicationBootstrap": 2,

server/src/nest/place-enrichment/place-enrichment.service.ts

@@ -907,6 +907,9 @@ export class PlaceEnrichmentService {
    * This is the same lookup the dialog already made when the user picked the
    * search result, and it is row-cached, so in practice it is a cache read
    * rather than a second provider call.
+   *
+   * @txStandalone the only write is the details row cache filling itself; a
+   * failure reads as no details and nothing else is written with it.
    */
   private async readDetails(
     userId: number,