fix(diagnostics-otel): export logs from diagnostic events

Export diagnostics OTEL logs through bounded diagnostic log events while keeping core log records off the public plugin diagnostic stream.\n\nIncludes security hardening for log payload redaction, bounded attributes, prototype-pollution keys, OTEL export failure reporting, and extension SDK seam usage.

src/plugin-sdk/diagnostics-otel.ts

@@ -3,7 +3,11 @@
 
 export type { DiagnosticEventPayload } from "../infra/diagnostic-events.js";
 export type { DiagnosticTraceContext } from "../infra/diagnostic-trace-context.js";
-export { emitDiagnosticEvent, onDiagnosticEvent } from "../infra/diagnostic-events.js";
+export {
+  emitDiagnosticEvent,
+  onDiagnosticEvent,
+  onInternalDiagnosticEvent,
+} from "../infra/diagnostic-events.js";
 export {
   createChildDiagnosticTraceContext,
   createDiagnosticTraceContext,