Show real photos for people instead of scene art

Your avatar is your photo, picked from the device by tapping it on Home or
from a new Profile photo row in Settings, shrunk to 256 px and kept on the
phone (there is no upload endpoint yet). Group members show the photo the
server sends in a new `photo` field, everywhere avatars appear. Without a
photo, an initial on a neutral disc. Mock mode bundles free Unsplash
portraits for the sample people.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01KhQh614DMeYoQEH9SoMRUw

frontend/lib/Grounded/designs/DotDigits.dart

@@ -82,11 +82,10 @@ class _DotDigitsPainter extends CustomPainter {
 
       final Path? outline = _glyph(glyph);
       if (outline != null) {
-        final Path placed = outline.transform(
-            (Matrix4.identity()
-                  ..translateByDouble(x, 0, 0, 1)
-                  ..scaleByDouble(_scale, _scale, 1, 1))
-                .storage);
+        final Path placed = outline.transform((Matrix4.identity()
+              ..translateByDouble(x, 0, 0, 1)
+              ..scaleByDouble(_scale, _scale, 1, 1))
+            .storage);
 
         for (PathMetric metric in placed.computeMetrics()) {
           final int count = (metric.length / gap).floor().clamp(1, 400);