test(street-level): fail only unexplained panel-press misses in CI

CI on fb024d5 failed step 24 with QA_FAIL_ON_RETRY=1: the press after a
double-click dock landed on the globe because the panel, showing a photo
that was still settling, moved 116 px up and lost 46 px of height between
the pre-press hit check and the press (box 1058,382 330x471 -> 1058,266
330x425, from the new diagnostics and the uploaded screenshot). That is
the panel's own content changing its layout, not the rail race fixed in
9dde7b4.

- Fail-on-retry now fails a miss only when the panel's box was the same
  at the hit check and at the press (the pointer missed a header that
  stood still); a miss the panel moving explains is retried with a
  ::warning:: naming the move. New harness test with a moving panel.
- Step 24 waits for the open photo and its sequence to finish loading
  before pressing the header again.

Verified: strict fixture gate on a production build 28 ok + 2 "no Google
3D" skips and the panel gate 6/6, both with QA_FAIL_ON_RETRY=1.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

scripts/qa-street-level.mjs

@@ -1660,6 +1660,9 @@ async function main() {
       await step(
         'collapsing a floating window docks it as the rail strip',
         async () => {
+          // The double-click just docked a panel showing a photo: let the photo
+          // and its sequence finish loading before pressing the header again.
+          await uiUntil((u) => !u.street.loading && !u.sequence.loading);
           await floatPanel();
           await page.click(
             '.panel-collapse-btn[data-collapse-target="street-level-panel"]',