Task #503: Stop home-screen Arabic labels from clipping letter dots on iPad

User report: in the Tx OS launcher, the dot above ج in "الاجتماعات"
(and similar diacritics on other tile labels) was being sliced off on
iPad — a visible visual-quality bug on the most-used screen.

Root cause (artifacts/tx-os/src/pages/home.tsx, AppIconContent):
the label span used `leading-tight` (line-height 1.25) + `truncate`
(overflow: hidden). At 11px the line-box was 13.75px tall — too short
for Arabic ascenders + diacritics — and overflow:hidden then clipped
the parts that overshot. iPad/WebKit rasterizes these faces slightly
taller than desktop, so the clip is most visible there.

Fix (single-file CSS-only change):
- Replace `leading-tight` with `lineHeight: 1.6` for plenty of room
  above the baseline.
- Add `paddingTop: 2` as cheap insurance for any remaining overshoot.
- Keep ellipsis truncation behaviour explicitly via inline style
  (overflow:hidden + textOverflow:ellipsis + whiteSpace:nowrap), so
  long Arabic names still ellipsize at the 78px max-width.
- Add `block` so max-width applies cleanly.

No change to icon tile size, grid layout, badges, or any other
markup. Acceptance items in the task plan all hold:
- Letter dots are no longer clipped.
- Long names still truncate with an ellipsis at 78px.
- Desktop layout is visually unchanged.

Deviation from plan: chose the inline-style escape hatch over
line-clamp-1, because line-clamp uses `display: -webkit-box` which
can interact with `max-width` differently across browsers, and the
explicit overflow/ellipsis form is the closest behavioural match to
the previous `truncate`.

artifacts/tx-os/src/pages/home.tsx

@@ -128,7 +128,16 @@ function AppIconContent({
           </span>
         )}
       </div>
-      <span className="text-[11px] text-foreground/85 font-medium text-center leading-tight max-w-[78px] truncate">
+      <span
+        className="text-[11px] text-foreground/85 font-medium text-center max-w-[78px] block"
+        style={{
+          lineHeight: 1.6,
+          paddingTop: 2,
+          overflow: "hidden",
+          textOverflow: "ellipsis",
+          whiteSpace: "nowrap",
+        }}
+      >
         {name}
       </span>
     </>