Route sidebar search icon directly to search (#5440)

## Thinking Path

> - Paperclip orchestrates AI agents for zero-human companies
> - Operators use the sidebar as their primary board navigation surface
> - The board now has a dedicated search page, so the header search icon
should behave as normal navigation instead of only dispatching a
command-palette shortcut
> - The Work nav also had a separate Search row, which duplicated the
always-visible header search affordance
> - This pull request keeps search one click away while making it a
direct `/search` link and reducing sidebar nav noise
> - The benefit is a smaller, clearer sidebar with search still
accessible from the top-level chrome

## What Changed

- Changed the sidebar header search icon into a direct `NavLink` to
`/search`.
- Removed the duplicate `Search` row from the Work navigation section.
- Added focused Sidebar coverage that asserts the header search link
target and confirms Search is not rendered in the Work nav.
- Refactored the Sidebar test setup helper to avoid repeating the React
Query wrapper across tests.

## Verification

- `pnpm install --frozen-lockfile` in the PR worktree so workspace
package symlinks existed for test execution. This completed with
existing plugin SDK bin warnings for missing built artifacts.
- `pnpm exec vitest run ui/src/components/Sidebar.test.tsx` — 3 passed.
- `pnpm --filter @paperclipai/ui typecheck` — passed.

## Risks

- Low: this changes a sidebar navigation affordance only. Users who
previously clicked the header icon now land on the full search page
instead of opening the command-palette shortcut path.
- Low: removing the Work nav Search row could affect users who expected
Search in that section, but the icon remains in the fixed sidebar header
and is covered by a targeted DOM test.

> For core feature work, check [`ROADMAP.md`](ROADMAP.md) first and
discuss it in `#dev` before opening the PR. Feature PRs that overlap
with planned core work may need to be redirected — check the roadmap
first. See `CONTRIBUTING.md`.

## Model Used

- OpenAI Codex coding agent, GPT-5 model family (`gpt-5`), tool-enabled
Paperclip heartbeat environment. Context window and internal reasoning
mode are not exposed by the runtime.

## Checklist

- [x] I have included a thinking path that traces from project context
to this change
- [x] I have specified the model used (with version and capability
details)
- [x] I have checked ROADMAP.md and confirmed this PR does not duplicate
planned core work
- [x] I have run tests locally and they pass
- [x] I have added or updated tests where applicable
- [x] If this change affects the UI, I have included before/after
screenshots or equivalent focused UI verification
- [x] I have updated relevant documentation to reflect my changes
- [x] I have considered and documented any risks above
- [x] I will address all Greptile and reviewer comments before
requesting merge

---------

Co-authored-by: Paperclip <noreply@paperclip.ing>

ui/src/components/IssueScheduledRetryCard.test.tsx

@@ -63,13 +63,13 @@ function buildRetryResponse(outcome: IssueRetryNowOutcome) {
   };
 }
 
-async function flushAll() {
-  for (let i = 0; i < 4; i += 1) {
-    // eslint-disable-next-line no-await-in-loop
+async function waitForUi(assertion: () => void) {
+  await vi.waitFor(async () => {
     await act(async () => {
       await Promise.resolve();
     });
-  }
+    assertion();
+  });
 }
 
 function renderWithProviders(ui: ReactNode) {
@@ -174,11 +174,12 @@ describe("IssueScheduledRetryCard", () => {
     act(() => {
       button!.click();
     });
-    await flushAll();
-    expect(retryNowMock).toHaveBeenCalledWith("issue-1");
-    const finalButton = getRetryNowButton();
-    expect(finalButton!.textContent ?? "").toContain("Promoted");
-    expect(finalButton!.disabled).toBe(true);
+    await waitForUi(() => {
+      expect(retryNowMock).toHaveBeenCalledWith("issue-1");
+      const finalButton = getRetryNowButton();
+      expect(finalButton!.textContent ?? "").toContain("Promoted");
+      expect(finalButton!.disabled).toBe(true);
+    });
   });
 
   it("shows already promoted state when backend reports duplicate click", async () => {
@@ -189,9 +190,10 @@ describe("IssueScheduledRetryCard", () => {
     act(() => {
       getRetryNowButton()!.click();
     });
-    await flushAll();
-    expect(getRetryNowButton()!.textContent ?? "").toContain("Already promoted");
-    expect(container.querySelector('[data-testid="issue-scheduled-retry-error-band"]')).toBeNull();
+    await waitForUi(() => {
+      expect(getRetryNowButton()!.textContent ?? "").toContain("Already promoted");
+      expect(container.querySelector('[data-testid="issue-scheduled-retry-error-band"]')).toBeNull();
+    });
   });
 
   it("renders an inline error band on backend failure", async () => {
@@ -202,11 +204,12 @@ describe("IssueScheduledRetryCard", () => {
     act(() => {
       getRetryNowButton()!.click();
     });
-    await flushAll();
-    const band = container.querySelector('[data-testid="issue-scheduled-retry-error-band"]');
-    expect(band).not.toBeNull();
-    expect((band?.textContent ?? "")).toContain("Server error");
-    expect(getRetryNowButton()!.disabled).toBe(false);
+    await waitForUi(() => {
+      const band = container.querySelector('[data-testid="issue-scheduled-retry-error-band"]');
+      expect(band).not.toBeNull();
+      expect((band?.textContent ?? "")).toContain("Server error");
+      expect(getRetryNowButton()!.disabled).toBe(false);
+    });
   });
 
   it("surfaces gate-suppressed outcome via the inline error band", async () => {
@@ -217,10 +220,11 @@ describe("IssueScheduledRetryCard", () => {
     act(() => {
       getRetryNowButton()!.click();
     });
-    await flushAll();
-    const band = container.querySelector('[data-testid="issue-scheduled-retry-error-band"]');
-    expect(band).not.toBeNull();
-    expect((band?.textContent ?? "")).toContain("Promotion suppressed");
-    expect(getRetryNowButton()!.disabled).toBe(false);
+    await waitForUi(() => {
+      const band = container.querySelector('[data-testid="issue-scheduled-retry-error-band"]');
+      expect(band).not.toBeNull();
+      expect((band?.textContent ?? "")).toContain("Promotion suppressed");
+      expect(getRetryNowButton()!.disabled).toBe(false);
+    });
   });
 });