feat(FN-2601): merge fusion/fn-2601 (auto-resolved)

- test(FN-2601): complete Step 3 — cover updated default copy
- feat(FN-2601): complete Step 2 — polish intro styling
- feat(FN-2601): complete Step 1 — update models tab copy

packages/dashboard/app/components/ModelSelectorTab.css

@@ -10,6 +10,9 @@
 .model-selector-intro {
   color: var(--text-muted);
   font-size: 13px;
+  line-height: 1.5;
+  border-left: var(--space-xs) solid var(--todo);
+  padding-left: var(--space-md);
   margin-bottom: var(--space-lg);
 }
 
@@ -23,7 +26,7 @@
 
 .model-selector-error {
   padding: var(--space-lg);
-  background: rgba(248, 81, 73, 0.1);
+  background: color-mix(in srgb, var(--color-error) 10%, transparent);
   color: var(--color-error);
   border-radius: var(--radius);
   font-size: 13px;

packages/dashboard/app/components/ModelSelectorTab.tsx

@@ -416,7 +416,7 @@ export function ModelSelectorTab({ task, addToast, onTaskUpdated, settings }: Mo
     <div className="model-selector-tab">
       <h4>Model Configuration</h4>
       <p className="model-selector-intro">
-        Override the AI models used for this task. When not specified, global default settings are used.
+        Override the AI models used for this task. When not specified, project or global defaults are used.
       </p>
 
       {modelsLoading ? (
@@ -571,7 +571,7 @@ export function ModelSelectorTab({ task, addToast, onTaskUpdated, settings }: Mo
 
           <div className="model-selector-status">
             {executorUsingDefault && validatorUsingDefault && planningUsingDefault && savedThinking === null
-              ? "Using global default models."
+              ? "Using project or global default models."
               : "Model settings are up to date."}
           </div>
         </>

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

@@ -127,6 +127,26 @@ describe("ModelSelectorTab", () => {
     expect(screen.queryByText("Reset")).not.toBeInTheDocument();
   });
 
+  it("shows updated intro copy mentioning project or global defaults", async () => {
+    render(<ModelSelectorTab task={FAKE_TASK} addToast={mockAddToast} />);
+
+    await waitForSelectors();
+
+    expect(
+      screen.getByText(
+        "Override the AI models used for this task. When not specified, project or global defaults are used.",
+      ),
+    ).toBeInTheDocument();
+  });
+
+  it("shows updated status copy when all selections use defaults", async () => {
+    render(<ModelSelectorTab task={FAKE_TASK} addToast={mockAddToast} />);
+
+    await waitForSelectors();
+
+    expect(screen.getByText("Using project or global default models.")).toBeInTheDocument();
+  });
+
   it("shows 'Using default' when no model overrides are set", async () => {
     render(<ModelSelectorTab task={FAKE_TASK} addToast={mockAddToast} />);