Resolve issue-3264: improve performance and documentation of unclaimed_sv_rewards (#3403)

fixes #3264
---------

Signed-off-by: Jose Velasco <jose.velasco@intellecteu.com>
Co-authored-by: moritzkiefer-da <45630097+moritzkiefer-da@users.noreply.github.com>

Author: jose-velasco-ieu

apps/app/src/test/scala/org/lfdecentralizedtrust/splice/integration/tests/UnclaimedSvRewardsScriptIntegrationTest.scala

@@ -183,6 +183,7 @@ class UnclaimedSvRewardsScriptIntegrationTest
               Seq(
                 "python",
                 "scripts/scan-txlog/unclaimed_sv_rewards.py",
+                "https://scan.sv-1.global.canton.network.invalid.com", // Intentionally invalid URL to simulate a down Scan server
                 sv1ScanBackend.httpClientConfig.url.toString(),
                 "--grace-period-for-mining-rounds-in-minutes",
                 "30",
@@ -253,6 +254,7 @@ class UnclaimedSvRewardsScriptIntegrationTest
               Seq(
                 "python",
                 "scripts/scan-txlog/unclaimed_sv_rewards.py",
+                "https://scan.sv-1.global.canton.network.invalid.com", // Intentionally invalid URL to simulate a down Scan server
                 sv1ScanBackend.httpClientConfig.url.toString(),
                 "--grace-period-for-mining-rounds-in-minutes",
                 "30",
@@ -322,6 +324,7 @@ class UnclaimedSvRewardsScriptIntegrationTest
               Seq(
                 "python",
                 "scripts/scan-txlog/unclaimed_sv_rewards.py",
+                "https://scan.sv-1.global.canton.network.invalid.com", // Intentionally invalid URL to simulate a down Scan server
                 sv1ScanBackend.httpClientConfig.url.toString(),
                 "--grace-period-for-mining-rounds-in-minutes",
                 "30",