Merge remote-tracking branch 'gh/main' into wave/tt22-no-legacy-json

# Conflicts:
#	context/test-evidence/command.md

harness/build.sh

@@ -22,7 +22,11 @@ serve="$root/harness/serve"
 # re-resolves the lock itself before any `-- --locked` reaches cargo build.
 # Fix a failure with `cargo update -w` in harness/opfs-contract, and commit it.
 cargo metadata --locked --format-version 1 \
-  --manifest-path "$root/harness/opfs-contract/Cargo.toml" >/dev/null
+  --manifest-path "$root/harness/opfs-contract/Cargo.toml" >/dev/null || {
+  echo "harness/build.sh: harness/opfs-contract/Cargo.lock is stale. Do not remove --locked." >&2
+  echo "  Run: cargo update -w --manifest-path harness/opfs-contract/Cargo.toml, and commit the lock." >&2
+  exit 1
+}
 
 "$root/web/build.sh" >/dev/null
 "$root/web/assemble.sh" "$serve" harness >/dev/null

harness/tests/help.spec.js

@@ -132,4 +132,30 @@ test.describe("the help overlay draws the shared content", () => {
     await expect(rows_.last().locator("td.selected")).toHaveCount(1);
     await expect(page.locator("#grid tbody td.selected")).toHaveCount(1);
   });
+
+  // improvise-1c5m. Below the width at which the app bar wraps, `#help` covers
+  // `#hint`, and Welcome itself says nothing about paging. The contract: the
+  // mode's own hint is UNCOVERED somewhere while help is open.
+  test("a narrow window still shows how to page through help", async ({ page }) => {
+    await page.setViewportSize({ width: 600, height: 800 });
+    await openHelp(page);
+
+    // The string is the page's own `#hint`, i.e. `hint_line(Help)`; this spec
+    // spells no keys. Asserting it names paging keeps an empty hint out.
+    const hint = (await page.locator("#hint").textContent()).trim();
+    expect(hint).toContain("next-page");
+
+    // An element showing exactly that string, topmost at its own centre: the
+    // overlay covering `#hint` is precisely what `elementFromPoint` sees.
+    const uncovered = await page.evaluate((text) =>
+      [...document.querySelectorAll("body *")].some((node) => {
+        if (node.children.length > 0 || node.textContent.trim() !== text) return false;
+        const r = node.getBoundingClientRect();
+        if (r.width === 0 || r.height === 0) return false;
+        const top = document.elementFromPoint(r.left + r.width / 2, r.top + r.height / 2);
+        return top !== null && (top === node || node.contains(top));
+      }),
+    hint);
+    expect(uncovered, "the paging hint is under the help overlay").toBe(true);
+  });
 });