feat(theme): add indigo (lunarpunk) accent + festival icons

Indigo palette for Solunar Society's night/festival character alongside
pine (city) and clay (farm); register Tent/Ticket/Sun/Moon/MapPin icons.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/deck/components/Icon.vue

@@ -24,6 +24,11 @@ import {
   Layers,
   Coins,
   HeartHandshake,
+  Tent,
+  Ticket,
+  Sun,
+  Moon,
+  MapPin,
   type LucideProps,
 } from '@lucide/vue'
 import type { FunctionalComponent } from 'vue'
@@ -52,6 +57,11 @@ const registry: Record<string, FunctionalComponent<LucideProps>> = {
   Layers,
   Coins,
   HeartHandshake,
+  Tent,
+  Ticket,
+  Sun,
+  Moon,
+  MapPin,
 }
 
 const props = defineProps<{ name: string }>()

src/style.css

@@ -93,6 +93,11 @@
   --color-amber-400: hsl(36 95% 60%);
   --color-amber-500: hsl(32 92% 52%);
 
+  /* lunarpunk / festival accent — Solunar Society (night) */
+  --color-indigo-300: hsl(255 85% 78%);
+  --color-indigo-400: hsl(256 78% 68%);
+  --color-indigo-500: hsl(258 70% 58%);
+
   --color-clay-400: hsl(14 72% 62%); /* farm / warmth accent */
   --color-sand: hsl(44 30% 90%); /* primary deck text */
   --color-sand-dim: hsl(150 8% 62%); /* muted deck text */