fix: tag counts, chip focus, upload naming, share links and unsized clips hold after round 2

- A tag counts the followed channels the Subscriptions tab shows: hidden ones are left out, and a
  subscribe, unsubscribe, hide or tag toggle refreshes the count. The Tag manager's row and its
  hover list count the same channels as the chip; /api/tags sends both counts under their names.
- A chip's count keeps the chip's colour after a dot (a dimmed count fell under 4.5:1). A pick in
  the open "+N" fold closes it; a chip that leaves the list hands the focus to the one in its place.
  The fold is a dialog of toggle buttons, not an empty menu.
- Upload: a folder name left by a press is made once the press is over, if the dialog is still
  open, instead of guessing a dismissal from Modal's markup. While the folder is made, its place
  holds the focus and a live region says so.
- Share: an expired link has no Copy and a warn badge; the link made on open goes into the cached
  list, so a reopen makes no second one; the New link form survives the link made on open.
- Watch: a repeated Enter sends one unlock while one is on its way. See all buttons are named with
  their rail.
- An unsized clip of a rotated file gets the upright size its crop cut.

frontend/src/lib/subscriptionCache.test.ts

@@ -21,9 +21,23 @@ describe("a subscription change", () => {
       qk.feedSummary(),
       qk.discoveredChannels(),
       qk.watchedChannels(),
+      qk.tags(),
     ]);
   });
 
+  // A tag counts the followed channels it is on, not hidden: a hide changes the number as an
+  // unsubscribe does, and both places that hide a channel must refresh it.
+  it("a hide refreshes the tags wherever it is made", () => {
+    const root = new URL("../", import.meta.url);
+    const sites = readdirSync(root, { recursive: true, encoding: "utf8" })
+      .map((f) => f.split("\\").join("/"))
+      .filter((f) => f.endsWith(".tsx") && !f.includes(".test.") && !f.startsWith("design-lab/"))
+      .map((f) => [f, readFileSync(new URL(f, root), "utf8")] as const)
+      .filter(([, src]) => /api\.updateChannel\([^)]*hidden/.test(src));
+    expect(sites.length).toBeGreaterThanOrEqual(2);
+    for (const [f, src] of sites) expect(src, f).toContain("queryKey: qk.tags()");
+  });
+
   it("is refreshed through that one function wherever it is made", () => {
     const root = new URL("../", import.meta.url);
     const sites = readdirSync(root, { recursive: true, encoding: "utf8" })