fix(panel): real auto-updating version + remove fake agent footer; rename companion -> Corrosion host agent

Version badge: was hardcoded '1.0.8' — now single-sourced from frontend/package.json (1.0.0) via Vite define __APP_VERSION__, so it auto-updates on release. Sidebar agent footer: removed the FABRICATED 'asgard-01' host name and the fake 'Agent v1.0.8' line — now shows real server.connection data, or an honest 'No host agent connected' empty state when nothing is deployed (the operator's actual state). Renamed 'Companion agent' -> 'Corrosion host agent' across the UI (ServerView/SetupWizard/Dashboard/Plugins), the binary names (corrosion-host-agent-<os>-<arch>) + CDN path (/host-agent/), the Go Makefile build output, and the Gitea CI workflow — frontend download links and CI output now match. Marketing hero mock host names neutralized (asgard-01 -> rust-host/dune-host/conan-host). DB column names (companion_last_seen) left intact. Build green; zero 'asgard'/'1.0.8' remain in frontend/src.

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

frontend/src/components/layout/DashboardLayout.vue

@@ -13,6 +13,7 @@ import { useServerStore } from '@/stores/server'
 import { useThemeGame } from '@/composables/useThemeGame'
 import { useGameProfile } from '@/config/gameProfiles'
 import type { NavSection, NavItemDef } from '@/config/gameProfiles'
+import { safeDate } from '@/utils/formatters'
 import Logo from '@/components/ds/brand/Logo.vue'
 import Badge from '@/components/ds/core/Badge.vue'
 import StatusDot from '@/components/ds/core/StatusDot.vue'
@@ -36,7 +37,7 @@ const sidebarOpen = ref(false)
 function closeSidebar() { sidebarOpen.value = false }
 
 // ---- App version ----
-const APP_VERSION = '1.0.8'
+const APP_VERSION = __APP_VERSION__
 
 // ---- Game switcher ----
 const GAME_OPTIONS: GameOption[] = [
@@ -94,6 +95,8 @@ function hasVisibleItems(section: NavSection): boolean {
 }
 
 // ---- Agent health ----
+const hasAgent = computed(() => server.connection !== null)
+
 const agentTone = computed(() => {
   const cs = server.connection?.connection_status
   if (cs === 'connected') return 'online' as const
@@ -106,9 +109,17 @@ const agentLabel = computed(() => {
   if (cs === 'degraded') return 'Degraded'
   return 'Offline'
 })
-const agentName = computed(() => {
-  const ip = server.connection?.server_ip
-  return ip ?? 'asgard-01'
+const agentName = computed(() => server.connection?.server_ip ?? 'Host agent')
+
+const agentMetaLine = computed(() => {
+  const cs = server.connection?.connection_status
+  let line = cs === 'connected' ? 'Connected' : server.connection?.companion_last_seen
+    ? `Last seen ${safeDate(server.connection.companion_last_seen)}`
+    : 'Awaiting first heartbeat'
+  if (server.stats) {
+    line += ` · ${server.stats.player_count}/${server.stats.max_players} players`
+  }
+  return line
 })
 
 // ---- Topbar ----
@@ -184,18 +195,24 @@ const themeIcon = computed(() => theme.value === 'dark' ? 'sun' : 'moon')
         </div>
       </nav>
 
-      <!-- Agent health footer -->
+      <!-- Host agent footer -->
       <div class="side__foot">
-        <div class="agent">
+        <!-- Connected: real IP + status badge + meta line -->
+        <div v-if="hasAgent" class="agent">
           <div class="agent__row">
             <StatusDot :tone="agentTone" :pulse="agentTone === 'online'" />
             <span class="agent__name">{{ agentName }}</span>
             <Badge :tone="agentTone" size="md">{{ agentLabel }}</Badge>
           </div>
-          <div class="agent__meta">
-            Agent v{{ APP_VERSION }}
-            <template v-if="server.stats"> · {{ server.stats.player_count }}/{{ server.stats.max_players }} players</template>
+          <div class="agent__meta">{{ agentMetaLine }}</div>
+        </div>
+        <!-- Not connected: honest empty state -->
+        <div v-else class="agent agent--empty">
+          <div class="agent__row">
+            <StatusDot tone="offline" />
+            <span class="agent__name agent__name--muted">No host agent connected</span>
           </div>
+          <div class="agent__meta">Install the Corrosion host agent from the Server page</div>
         </div>
         <!-- User / logout row -->
         <div class="side__user">
@@ -373,6 +390,13 @@ body { margin: 0; overflow: hidden; }
   padding-left: 16px;
 }
 
+.agent--empty { opacity: 0.7; }
+
+.agent__name--muted {
+  color: var(--text-tertiary);
+  font-style: italic;
+}
+
 .side__user {
   display: flex;
   align-items: center;