Composes the one Layer-0 hop existing tests left uncovered together:
ScriptLogSignalRBridge subscribing to the script-logs DPS topic and
fanning a ScriptLogEntry out to the IInProcessBroadcaster<ScriptLogEntry>
singleton resolved from the SAME DI container the /script-log page injects.
Mirrors DriverStatusHubE2eTests. Confirms the server-side topic→page chain
delivers end-to-end (only the live Blazor circuit remains manual).
Joseph Doherty