Wraps IExternalSystemClient.CallAsync inside ScriptRuntimeContext's
ExternalSystemHelper so every script-initiated ExternalSystem.Call
produces exactly one ApiOutbound/ApiCall AuditEvent via IAuditWriter.
- Captures duration with Stopwatch.GetTimestamp() around the call.
- Builds the audit event with full provenance (SiteId, InstanceId,
SourceScript) and a fresh EventId; ForwardState=Pending.
- Maps Success → AuditStatus.Delivered, Failure (or thrown) → Failed;
parses HTTP {code} out of the ExternalSystemClient's error message
to populate HttpStatus.
- Audit emission is fully best-effort: event-build failures, sync
WriteAsync throws, AND async WriteAsync faults are all logged at
Warning and swallowed so the script's call path is never aborted
by an audit-write failure (alog.md §7).
- Original ExternalCallResult or original exception flows back to the
caller unchanged.
ScriptExecutionActor resolves IAuditWriter from DI and threads it
into ScriptRuntimeContext alongside the existing site identity.
Adds ExternalSystemCallAuditEmissionTests covering: success →
Delivered, HTTP 500 → Failed+httpStatus, HTTP 400 → Failed+httpStatus,
client-thrown network exception → Failed with original exception
re-thrown, audit-writer throw → original result returned, provenance
populated from context, DurationMs recorded.
Refs Audit Log #23 M2 Bundle F.
82a8bbf225