refactor: replace maxRounds with supervisor check interval

Removes maxRounds as a hard stop limit from the entire stack. The supervisor
(already configured via workflow.yaml supervisorInterval) is now the sole
termination authority.

Changes across 27 files in 11 packages:
- workflow-protocol: StartStep.meta is now empty, StartNodePayload drops maxRounds
- workflow-cas: isStartPayload no longer checks maxRounds
- workflow-execute: engine, worker, fork-thread all stripped of maxRounds plumbing
- cli-workflow: --max-rounds flag removed from CLI and HTTP API
- workflow-runtime: build-context and create-workflow no longer reference maxRounds
- workflow-dashboard: UI no longer sends maxRounds
- workflow-template-develop/solve-issue: moderator no longer checks rounds remaining
- All tests updated

Fixes #185

packages/workflow-runtime/__tests__/build-context.test.ts

@@ -27,7 +27,7 @@ describe("buildThreadContext", () => {
     const bundleHash = "BHAAAAAAAAAAA";
     const startHash = await putStartNode(
       cas,
-      { name: "demo", hash: bundleHash, maxRounds: 99, depth: 2 },
+      { name: "demo", hash: bundleHash, depth: 2 },
       promptHash,
     );
 
@@ -59,7 +59,6 @@ describe("buildThreadContext", () => {
     expect(ctx.depth).toBe(2);
     expect(ctx.start.role).toBe(START);
     expect(ctx.start.content).toBe("hello-task");
-    expect(ctx.start.meta.maxRounds).toBe(99);
     expect(ctx.steps.map((s) => s.role)).toEqual(["planner", "coder"]);
     expect(ctx.steps[0]?.refs).toEqual([art]);
     expect(ctx.steps[1]?.refs).toEqual([]);
@@ -72,7 +71,7 @@ describe("buildThreadContext", () => {
     const promptHash = await cas.put("only-prompt");
     const startHash = await putStartNode(
       cas,
-      { name: "solo", hash: "BHBBBBBBBBBBB", maxRounds: 3, depth: 1 },
+      { name: "solo", hash: "BHBBBBBBBBBBB", depth: 1 },
       promptHash,
     );
 
@@ -80,7 +79,6 @@ describe("buildThreadContext", () => {
     expect(ctx.steps).toEqual([]);
     expect(ctx.start.content).toBe("only-prompt");
     expect(ctx.depth).toBe(1);
-    expect(ctx.start.meta.maxRounds).toBe(3);
   });
 
   test("omits __end__ states from steps", async () => {
@@ -89,7 +87,7 @@ describe("buildThreadContext", () => {
     const bundleHash = "BHCCCCCCCCCCC";
     const startHash = await putStartNode(
       cas,
-      { name: "demo", hash: bundleHash, maxRounds: 10, depth: 0 },
+      { name: "demo", hash: bundleHash, depth: 0 },
       promptHash,
     );
 

packages/workflow-runtime/src/build-context.ts

@@ -57,7 +57,7 @@ async function threadFromStartHead<M extends RoleMeta>(
     start: {
       role: START,
       content: prompt,
-      meta: { maxRounds: p.maxRounds },
+      meta: {},
       timestamp: 0,
     },
     steps: [],
@@ -116,7 +116,7 @@ async function threadFromStateHead<M extends RoleMeta>(
     start: {
       role: START,
       content: prompt,
-      meta: { maxRounds: sp.maxRounds },
+      meta: {},
       timestamp: firstTs,
     },
     steps,

packages/workflow-runtime/src/create-workflow.ts

@@ -101,9 +101,10 @@ async function advanceOneRound<M extends RoleMeta>(
   );
   const artifactRefs = mergeUniqueHashes(extracted.refs, refsFromMeta);
 
-  const contentHash = artifactRefs.length === 0
-    ? agentContentHash
-    : await putContentNodeWithRefs(runtime.cas, extracted.contentPayload, artifactRefs);
+  const contentHash =
+    artifactRefs.length === 0
+      ? agentContentHash
+      : await putContentNodeWithRefs(runtime.cas, extracted.contentPayload, artifactRefs);
   const refs = artifactRefs.includes(contentHash) ? artifactRefs : [...artifactRefs, contentHash];
 
   const step = {
@@ -144,17 +145,9 @@ export function createWorkflow<M extends RoleMeta>(
     if (thread.start.role !== START) {
       throw new Error(`workflow loop expected start role to be ${START}`);
     }
-    const maxRounds = thread.start.meta.maxRounds;
     let currentThread = thread as ModeratorContext<M>;
 
     while (true) {
-      if (currentThread.steps.length >= maxRounds) {
-        return {
-          returnCode: 0,
-          summary: `completed: reached maxRounds (${maxRounds})`,
-        };
-      }
-
       const outcome = await advanceOneRound(def, binding, {
         thread: currentThread,
         runtime,