feat: HomeDash - unified self-hosted navigation portal

Single-container navigation service combining:
- Dashy dashboard + SearXNG metasearch + history sync API + admin WebUI
- Go services for history/admin APIs, nginx as unified entry
- Browser extensions (Chrome MV3 / Firefox MV2) with 30s batched sync
- Production guide: portal-nginx unified auth reverse proxy + webui4frpc/frp tunnel
- Fully sanitized (no internal IPs/domains/credentials)

conf.example.yml

@@ -0,0 +1,53 @@
+appConfig:
+  theme: default
+  dayTheme: default
+  nightTheme: midnight
+  customColors: {}
+  externalStyleSheet: []
+  webSearch:
+    searchEngine: custom
+    customSearchEngine: /search?q=
+    openingMethod: newtab
+  customCss: ""
+layout: masonry
+iconSize: large
+language: zh-CN
+statusCheck: true
+statusCheckInterval: 60
+
+pageInfo:
+  title: Navigation Portal
+  description: Self-hosted unified navigation
+  navLinks: []
+  footer: ""
+
+sections:
+  - name: Code Hosting
+    icon: fas fa-code-branch
+    collapsed: false
+    items:
+      - title: Gitea
+        description: Code repository
+        icon: fas fa-code-branch
+        url: http://192.168.1.100:3000
+        statusCheck: true
+
+  - name: History
+    icon: fas fa-history
+    collapsed: false
+    items:
+      - title: Install browser extension...
+        description: History fills automatically after sync
+        icon: fas fa-info-circle
+        url: /admin/
+
+  - name: Tools
+    icon: fas fa-tools
+    collapsed: true
+    items:
+      - title: Example Service
+        description: Add your own services
+        icon: fas fa-cog
+        url: http://192.168.1.100:8080
+
+pages: []