Rename Sommer/Winter to Sommerräder/Winterräder, reflow Reifen tile headline

The tile headline now reads "Sommerräder"/"Winterräder" and renders as an
actual headline (new .tile-headline class, 20px/var(--fg)) instead of the
small muted .label styling used for other in-tile section titles.

Headline + km now sit above "Montiert" instead of the wheel photo
overlaying it: new .radkopf-row (flex) puts headline/km and the photo
side by side at the tile's top; Montiert dropped position:absolute (no
longer needed once the photo stopped sharing its space) and is now a
normal-flow pill below the headline block.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

AGENTS.md

@@ -1019,6 +1019,24 @@ wraps the web app for iPhone; a PWA home-screen install is the accepted intermed
       the ios one at matching specificity, but fixed too rather than left as a landmine). Verified live
       via screenshot: all 5 tab icons render correctly in icon-only mode, active tab still shows its
       filled pill.
+- [x] Eighth round the same day (2026-08-16) — Reifen tile relabel + reflow, per explicit request:
+      "Sommer"/"Winter" → **"Sommerräder"/"Winterräder"** (only the section headline text in
+      `vReifen()`'s `satz()`; the singular "Sommerrad"/"Winterrad" photo label and the `data-satz`
+      value compared against `CAR.reifen.aktiv` elsewhere were deliberately left untouched — the first
+      is grammatically correct as-is for a single wheel photo, the second is an internal state key, not
+      display text, and changing it would break the mount-toggle matching in the `[data-satz]` click
+      handler). That headline is now an actual **headline** — new `.tile-headline` class (20px,
+      `var(--fg)`, same typographic family as the page `.title` one step down) replacing the small,
+      muted `.label` styling every other in-tile section title uses.
+      Reflowed so the headline+km sit **above** "Montiert" instead of the wheel photo overlaying it:
+      new `.radkopf-row` (flex, `justify-content:space-between`) puts the headline/km block and the
+      wheel photo side by side at the tile's top, both top-aligned; `.montiert` dropped `position:
+      absolute` (no longer needs to float over the photo now that the photo isn't in that space) and
+      became a normal-flow pill with `margin-top` under the headline block — simpler than the previous
+      overlay hack, same 44×44pt invisible tap target via `::before`. `.bildbox.radbild`'s `margin-
+      left:auto` (added last round to right-align it under its old block-flow parent) was removed since
+      `.radkopf-row`'s flex layout does that job now. Deployed to `audi_ha_test`, confirmed live via
+      screenshot for both Sommerräder (mounted) and Winterräder (unmounted) tiles.
 - [ ] Fix remaining documentation drift (statistics claim, README gaps, obsolete TODO comment) —
       text-only changes; INSTALL.md's WLAN/TommiG1 drift and stale variable names were fixed
       2026-08-12 (see section B); `DESIGN_REVIEW_2026-08-13.md` and `REVIEW_main_2026-08-13.md`