feat(core,server,docs): default max_turns to -1 (unlimited) to avoid unexpected run cutoffs (#232)

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

packages/core/test/goal.test.ts

@@ -297,6 +297,20 @@ describe("runGoalLoop", () => {
     expect(await readGoalStatus(file)).toBe("active");
   });
 
+  it("an explicit maxRounds of -1 disables the backstop: the goal runs past 100 rounds", async () => {
+    // The default backstop stays 100; -1 is the explicit opt-out. Round 103 claims
+    // complete, which the default cap would have ended as `aborted` at round 100.
+    const behaviors = Array.from({ length: 103 }, (_, i) =>
+      i === 102 ? { then: () => setStatus("complete") } : {},
+    );
+    const session = fakeSession(behaviors);
+    const { outcome } = await drain(
+      runGoalLoop(session, { text: "o", goalFilePath: file, maxRounds: -1 }),
+    );
+    expect(outcome).toEqual({ outcome: "complete", rounds: 103, tokensUsed: 0 });
+    expect(session.prompts).toHaveLength(103);
+  });
+
   it("an abort landing between rounds stops the loop without a phantom round", async () => {
     const ac = new AbortController();
     // The signal aborts AFTER round 1's stream ends — no abort event ever hits the stream,