fix(plugins): keep the release-only runtime-llm ownership and isolated-reasoning tests green (#156565)

Operator authority currency no longer folds the caller's own abort signal into
assertCurrent, so a caller-aborted direct completion settles through the
provider result again instead of rejecting after the stream ended (regressed
in #156346). The isolated reasoning validation fixture uses max, which stays
unsupported for the host-resolved model now that Ultra is a harness mode on
every runtime (#155393).

Co-authored-by: Peter Steinberger <studpete@gmail.com>

src/plugins/runtime/runtime-llm-isolated.runtime.test.ts

@@ -364,7 +364,7 @@ describe("runtime.llm.complete isolated agent runtime", () => {
     await expect(
       llm.complete({
         messages: [{ role: "user", content: "Return JSON" }],
-        reasoning: "ultra",
+        reasoning: "max",
         execution: { mode: "isolated-agent-runtime" },
       }),
     ).rejects.toMatchObject({ code: "LLM_ISOLATED_INPUT_REJECTED" });

src/plugins/runtime/runtime-llm-operator-authority.ts

@@ -32,7 +32,7 @@ export function bindLlmOperatorAuthority(
       if (hostCaller?.kind === "context-engine") {
         return await complete(params, {
           signal: params.signal,
-          assertCurrent: () => params.signal?.throwIfAborted(),
+          assertCurrent: () => {},
           bindModelExecution: () => undefined,
         });
       }
@@ -55,10 +55,10 @@ export function bindLlmOperatorAuthority(
           ? AbortSignal.any([params.signal, operatorAuthority.signal])
           : operatorAuthority.signal
         : params.signal;
+      // Operator currency only: the caller's own abort settles through the provider result.
       const assertCurrent = () => {
         capturedOperator.assertInvocationCurrent?.();
         operatorAuthority?.assertCurrent();
-        signal?.throwIfAborted();
       };
       assertCurrent();
       return await complete(params, {