fix(api): harden optional audit and session fields

packages/api/src/router/utilization-category-procedure-support.ts

@@ -74,7 +74,7 @@ export async function createUtilizationCategory(
     entityId: created.id,
     entityName: created.name,
     action: "CREATE",
-    userId: ctx.dbUser?.id,
+    ...(ctx.dbUser?.id ? { userId: ctx.dbUser.id } : {}),
     after: created as unknown as Record<string, unknown>,
     source: "ui",
   });
@@ -112,7 +112,7 @@ export async function updateUtilizationCategory(
     entityId: updated.id,
     entityName: updated.name,
     action: "UPDATE",
-    userId: ctx.dbUser?.id,
+    ...(ctx.dbUser?.id ? { userId: ctx.dbUser.id } : {}),
     before,
     after: updated as unknown as Record<string, unknown>,
     source: "ui",