Palette: seven roles (accent, good, caution added; highlight renamed alarm); no hard-coded colours left

background, foreground, subdued, accent (emphasis without danger), and the state
gradient good → caution → alarm; surface and onFill derived. smart-serow's
four-key themes still load (highlight = alarm; the new roles fall back).
Material's scheme follows: buttons in accent instead of the alarm colour.
Link state, mock banner, signal tiles, raw log, checklist button and marks,
camera page all take palette roles.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DDwfd6Ki8UfG4hK6W5YpJz

assets/themes/default.json

@@ -2,13 +2,19 @@
   "dark": {
     "background": "#000000",
     "foreground": "#FFFFFF",
-    "highlight": "#FF5555",
-    "subdued": "#808080"
+    "subdued": "#808080",
+    "accent": "#5EC8F2",
+    "good": "#6CCB5F",
+    "caution": "#FFC107",
+    "alarm": "#FF5555"
   },
   "bright": {
     "background": "#F0F0F0",
     "foreground": "#1A1A1A",
-    "highlight": "#CC0000",
-    "subdued": "#606060"
+    "subdued": "#606060",
+    "accent": "#0277BD",
+    "good": "#2E7D32",
+    "caution": "#8D6E00",
+    "alarm": "#CC0000"
   }
 }