Credit the import-contacts onboarding reward on account connection (#22354)

Onboarding V2 shows a credit reward for connecting an email account, but
the reward was only ever a frontend localStorage counter, never granted
server-side. This applies it for real.

When the connect-account step is actually completed via a Google or
Microsoft connection, the workspace is credited
`ONBOARDING_IMPORT_CONTACTS_CREDITS_REWARD`. Eligibility is derived
server-side from the `ONBOARDING_CONNECT_ACCOUNT_PENDING` flag (set once
at workspace creation), so the reward is one-time and is not granted
when the step is skipped. Crediting is best-effort: it never blocks the
OAuth flow and no-ops when billing is disabled.

The invite-team reward is handled separately in #22309. The upgrade
reward needs no grant: it is applied structurally through the trial
resource-usage cap, so an explicit grant would double-count it.


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packages/twenty-server/src/engine/core-modules/key-value-pair/key-value-pair.service.ts

@@ -132,12 +132,12 @@ export class KeyValuePairService<
       key,
     };
 
-    if (queryRunner) {
-      await queryRunner.manager
-        .getRepository(KeyValuePairEntity)
-        .delete(deleteConditions);
-    } else {
-      await this.keyValuePairRepository.delete(deleteConditions);
-    }
+    const { affected } = queryRunner
+      ? await queryRunner.manager
+          .getRepository(KeyValuePairEntity)
+          .delete(deleteConditions)
+      : await this.keyValuePairRepository.delete(deleteConditions);
+
+    return affected;
   }
 }