feat(design): a library row keeps Share (the link copy) in sight, ahead of save (E28 S3e3)

The owner's call: sharing a download's link is the library's main errand, more
important than saving the file, so it does not hide in the row's "…". Manage
sharing stays in the menu. The "…" tests press as a mouse, so a stray long-press
timer no longer fires after teardown.

frontend/src/components/VideoMenu.dom.test.tsx

@@ -190,7 +190,7 @@ describe("a video's menu", () => {
     expect(more().getAttribute("aria-expanded")).toBe("true");
     // The press lands outside the panel, which floating-ui's dismiss closes on; the click after
     // it must not open it again.
-    fireEvent.pointerDown(more());
+    fireEvent.pointerDown(more(), { pointerType: "mouse" });
     fireEvent.mouseDown(more());
     fireEvent.click(more(), { detail: 1 });
     expect(labels()).toEqual([]);
@@ -200,7 +200,7 @@ describe("a video's menu", () => {
     setup(video({}));
     fireEvent.click(more(), { detail: 1 });
     // A press on the open row's "…" that never became a click (released elsewhere)…
-    fireEvent.pointerDown(more());
+    fireEvent.pointerDown(more(), { pointerType: "mouse" });
     fireEvent.keyDown(document, { key: "Escape" });
     // …then Enter on the button: a click with no pointer (detail 0).
     fireEvent.click(more(), { detail: 0 });