FN-5797: fix usage indicator show hidden button behavior

Prevent hidden-window controls in UsageIndicator from acting as implicit form submitters.

- Set both window-level Hide and provider-level Show hidden buttons to `type="button"`.
- Preserve hidden-window reveal behavior without submitting parent forms.
- Add a regression test covering hide/show persistence and rerender re-sync behavior.

Files changed:
 .changeset/fn-5797-show-hidden-fix.md              |  8 +++++
 packages/dashboard/app/components/UsageIndicator.tsx    |  2 ++
 packages/dashboard/app/components/__tests__/UsageIndicator.test.tsx   | 40 ++++++++++++++++++++++
 3 files changed, 50 insertions(+)

Fusion-Task-Id: FN-5797

Fusion-Task-Lineage: 9072bb68-b86b-4ec7-8b1f-0e6b706cbb5f

.changeset/fn-5797-show-hidden-fix.md

@@ -0,0 +1,8 @@
+---
+"@runfusion/fusion": patch
+---
+
+Fixes the UsageIndicator popup hidden-window recovery flow by preventing hide/show controls from acting as implicit form-submit buttons.
+
+- Sets the per-window hide control and provider-level **Show hidden (N)** control to `type="button"` so they do not trigger parent form submits.
+- Adds a regression test that verifies clicking **Show hidden** reveals hidden windows, persists the unhidden state, and remains correct after rerender/state re-sync.

packages/dashboard/app/components/UsageIndicator.tsx

@@ -238,6 +238,7 @@ function UsageWindowRow({ window, viewMode, isHidden, onToggleHidden }: UsageWin
           {!isHidden && <span className="usage-window-percentage">{headerText}</span>}
           {!isHidden && (
             <button
+              type="button"
               className="btn-icon usage-window-hide-btn"
               onClick={onToggleHidden}
               aria-label={`Hide ${window.label}`}
@@ -444,6 +445,7 @@ function ProviderCard({
           <span className="usage-provider-name">{provider.name}</span>
           {hiddenCount > 0 && (
             <button
+              type="button"
               className="btn btn-sm usage-show-hidden-btn"
               onClick={() => onShowAllHidden(provider.name)}
               data-testid="usage-show-hidden-btn"

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

@@ -979,6 +979,46 @@ describe("UsageIndicator", () => {
     expect(screen.getByRole("button", { name: "Hide Weekly" })).toBeInTheDocument();
   });
 
+  it("show hidden remains revealed across rerender and does not submit parent forms", () => {
+    mockUseUsageData.mockReturnValue({
+      providers: mockProviders,
+      loading: false,
+      error: null,
+      lastUpdated: new Date(),
+      refresh: mockRefresh,
+    });
+
+    const onSubmit = vi.fn((event: Event) => {
+      event.preventDefault();
+    });
+
+    const { rerender } = render(
+      <form onSubmit={onSubmit}>
+        <UsageIndicator isOpen={true} onClose={mockOnClose} projectId={TEST_PROJECT_ID} />
+      </form>
+    );
+
+    fireEvent.click(screen.getByRole("button", { name: "Hide Session (5h)" }));
+    expect(localStorage.getItem(USAGE_HIDDEN_WINDOWS_KEY)).toBe(
+      JSON.stringify({ Anthropic: ["Session (5h)"] })
+    );
+
+    fireEvent.click(screen.getByTestId("usage-show-hidden-btn"));
+
+    expect(onSubmit).not.toHaveBeenCalled();
+    expect(localStorage.getItem(USAGE_HIDDEN_WINDOWS_KEY)).toBe(JSON.stringify({}));
+    expect(screen.getByText("Session (5h)").closest(".usage-window")).not.toHaveClass("usage-window--hidden");
+
+    rerender(
+      <form onSubmit={onSubmit}>
+        <UsageIndicator isOpen={true} onClose={mockOnClose} projectId={TEST_PROJECT_ID} />
+      </form>
+    );
+
+    expect(screen.queryByTestId("usage-show-hidden-btn")).not.toBeInTheDocument();
+    expect(screen.getByText("Session (5h)").closest(".usage-window")).not.toHaveClass("usage-window--hidden");
+  });
+
   it("does not show provider-level show hidden button when no windows are hidden", () => {
     mockUseUsageData.mockReturnValue({
       providers: mockProviders,