Fix tasks page scroll reset

Co-Authored-By: Paperclip <noreply@paperclip.ing>

ui/src/lib/navigation-scroll.test.ts

@@ -41,6 +41,37 @@ describe("navigation-scroll", () => {
     ).toBe(false);
   });
 
+  it("resets scroll when navigating into the top-level issues page", () => {
+    expect(
+      shouldResetScrollOnNavigation({
+        previousPathname: "/issues/PAP-1389",
+        pathname: "/issues",
+        navigationType: "PUSH",
+        state: null,
+      }),
+    ).toBe(true);
+
+    expect(
+      shouldResetScrollOnNavigation({
+        previousPathname: "/PAP/issues/PAP-1389",
+        pathname: "/PAP/issues",
+        navigationType: "REPLACE",
+        state: null,
+      }),
+    ).toBe(true);
+  });
+
+  it("does not reset issues page scroll on browser history restoration", () => {
+    expect(
+      shouldResetScrollOnNavigation({
+        previousPathname: "/issues/PAP-1389",
+        pathname: "/issues",
+        navigationType: "POP",
+        state: null,
+      }),
+    ).toBe(false);
+  });
+
   it("resets scroll when navigating directly between issue detail routes", () => {
     expect(
       shouldResetScrollOnNavigation({

ui/src/lib/navigation-scroll.ts

@@ -14,6 +14,7 @@ export function shouldResetScrollOnNavigation(params: {
   if (previousPathname === null) return false;
   if (previousPathname === pathname) return false;
   if (navigationType === "POP") return false;
+  if (isIssueIndexPath(pathname)) return true;
   if (isIssueDetailPathChange(previousPathname, pathname)) return true;
   return hasSidebarScrollResetState(state);
 }
@@ -75,6 +76,14 @@ function isIssueDetailPathChange(previousPathname: string, pathname: string): bo
   return previousIssueRef !== null && nextIssueRef !== null && previousIssueRef !== nextIssueRef;
 }
 
+function isIssueIndexPath(pathname: string): boolean {
+  const segments = pathname.split("/").filter(Boolean);
+  return (
+    (segments.length === 1 && segments[0] === "issues")
+    || (segments.length === 2 && segments[1] === "issues")
+  );
+}
+
 function readIssueDetailPathRef(pathname: string): string | null {
   const segments = pathname.split("/").filter(Boolean);
   if (segments.length === 2 && segments[0] === "issues") {