feat(redesign): design-system tokens, 23 Vue components, game-aware shell + Fleet/Solo dashboard

Tokens ported 1:1 from the Claude Design bundle (colors/game-themes/type/spacing/elevation/motion/fonts) with the data-theme/data-game theming contract via useThemeGame (+ cc-skin-swap repaint guard). 23 design-system components reimplemented as Vue SFCs (core/forms/data/navigation/feedback/brand). DashboardLayout rebuilt as the game-aware shell (GameSwitcher, grouped nav with permission gating preserved, agent-health footer, topbar). DashboardView: Fleet + Solo with per-game GAME_FIELDS rows and the themed ECharts PlayersChart; Solo wired to the real server store, Fleet on representative data pending the multi-instance backend. All four game skins (Rust/Dune/Conan/Soulmask). vue-tsc + vite build green.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

frontend/src/components/ds/navigation/NavItem.vue

@@ -0,0 +1,50 @@
+<script setup lang="ts">
+/**
+ * NavItem — sidebar navigation row: icon + label, active state with accent rail,
+ * optional trailing count. Collapsed mode renders icon-only at 40 px wide.
+ */
+import Icon from '@/components/ds/core/Icon.vue'
+
+withDefaults(
+  defineProps<{
+    icon: string
+    label: string
+    active?: boolean
+    count?: number | string
+    collapsed?: boolean
+  }>(),
+  { active: false, collapsed: false },
+)
+
+const emit = defineEmits<{ click: [] }>()
+</script>
+
+<template>
+  <div
+    :class="['cc-nav', active && 'cc-nav--active', collapsed && 'cc-nav--collapsed']"
+    role="button"
+    :aria-current="active ? 'page' : undefined"
+    :title="collapsed ? label : undefined"
+    @click="emit('click')"
+  >
+    <span class="cc-nav__icon">
+      <Icon :name="icon" :size="17" :stroke-width="2" />
+    </span>
+    <span v-if="!collapsed" class="cc-nav__label">{{ label }}</span>
+    <span v-if="!collapsed && count != null" class="cc-nav__count">{{ count }}</span>
+  </div>
+</template>
+
+<style>
+.cc-nav { display:flex; align-items:center; gap:10px; height:34px; padding:0 10px; border-radius:var(--radius-md);
+  color:var(--text-secondary); cursor:pointer; transition:var(--transition-colors); position:relative; user-select:none; }
+.cc-nav:hover { background:var(--surface-hover); color:var(--text-primary); }
+.cc-nav__icon { flex:none; color:var(--text-tertiary); display:flex; transition:var(--transition-colors); }
+.cc-nav__label { flex:1; font-size:var(--text-sm); font-weight:500; white-space:nowrap; overflow:hidden; text-overflow:ellipsis; }
+.cc-nav__count { font-family:var(--font-mono); font-size:11px; color:var(--text-tertiary); padding:1px 6px; border-radius:var(--radius-pill); background:var(--surface-active); }
+.cc-nav--active { background:var(--accent-soft); color:var(--accent-text); }
+.cc-nav--active .cc-nav__icon { color:var(--accent-text); }
+.cc-nav--active::before { content:''; position:absolute; left:-10px; top:7px; bottom:7px; width:3px; border-radius:var(--radius-pill); background:var(--accent); }
+.cc-nav--active .cc-nav__count { background:var(--accent-soft-strong); color:var(--accent-text); }
+.cc-nav--collapsed { justify-content:center; padding:0; width:40px; }
+</style>