fix(FN-2586): restore 0.4.x release line and agent log stability

packages/dashboard/app/components/AgentLogViewer.tsx

@@ -185,26 +185,6 @@ export function AgentLogViewer({
     }
   }, [isFullscreen, handleKeyDown]);
 
-  if (loading && entries.length === 0) {
-    return (
-      <div className="agent-log-viewer" data-testid="agent-log-viewer">
-        <div className="agent-log-loading">Loading agent logs…</div>
-      </div>
-    );
-  }
-
-  if (entries.length === 0) {
-    return (
-      <div className="agent-log-viewer" data-testid="agent-log-viewer">
-        <div className="agent-log-empty">No agent output yet.</div>
-      </div>
-    );
-  }
-
-  // Reverse entries so newest appear first
-  const reversedEntries = [...entries].reverse();
-  const reversedEntryKeys = [...chronologicalEntryKeys].reverse();
-
   const hasExecutorOverride = executorModel?.provider && executorModel?.modelId;
   const hasValidatorOverride = validatorModel?.provider && validatorModel?.modelId;
   const hasPlanningOverride = planningModel?.provider && planningModel?.modelId;
@@ -242,6 +222,26 @@ export function AgentLogViewer({
     planningModel,
   ]);
 
+  if (loading && entries.length === 0) {
+    return (
+      <div className="agent-log-viewer" data-testid="agent-log-viewer">
+        <div className="agent-log-loading">Loading agent logs…</div>
+      </div>
+    );
+  }
+
+  if (entries.length === 0) {
+    return (
+      <div className="agent-log-viewer" data-testid="agent-log-viewer">
+        <div className="agent-log-empty">No agent output yet.</div>
+      </div>
+    );
+  }
+
+  // Reverse entries so newest appear first
+  const reversedEntries = [...entries].reverse();
+  const reversedEntryKeys = [...chronologicalEntryKeys].reverse();
+
   return (
     <div
       ref={containerRef}

packages/dashboard/app/components/__tests__/AgentLogViewer.test.tsx

@@ -36,6 +36,19 @@ describe("AgentLogViewer", () => {
     expect(screen.getByText("No agent output yet.")).toBeTruthy();
   });
 
+  it("rerenders from empty state to populated logs without changing hook order", () => {
+    const consoleErrorSpy = vi.spyOn(console, "error").mockImplementation(() => {});
+    const entry = makeEntry({ text: "streamed chunk" });
+    const { rerender } = render(<AgentLogViewer entries={[]} loading={false} />);
+
+    expect(() => {
+      rerender(<AgentLogViewer entries={[entry]} loading={false} />);
+    }).not.toThrow();
+
+    expect(screen.getByText("streamed chunk")).toBeTruthy();
+    consoleErrorSpy.mockRestore();
+  });
+
   it("renders text entries as spans in reverse order (newest first)", () => {
     const entries = [
       makeEntry({ text: "first chunk" }),