feat: hash路由 + 插件页面内联加载 + 侧边栏插件面板展开项

- Hash路由: #/dashboard #/files #/plugins/xxx 支持刷新保持/前进后退
- 登录过期保留hash,登录后自动跳回原页面
- 插件WebUI页面内联加载到page-container(不再弹新窗)
- 插件页面HTML自动处理: style提取/body剥离/script执行/padding归零
- 侧边栏新增「插件面板」可折叠项,展开列出所有已注册插件页面
- 内存卡片显示 已用/总容量(百分比右侧)
- 插件开发指南新增 2.6 WebUI页面开发章节

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

services/web_panel/routes/plugins.py

@@ -8,6 +8,7 @@ logger = logging.getLogger(__name__)
 
 def setup_routes(app, prefix=''):
     app.router.add_get(f'{prefix}/api/plugins', panel_auth(list_plugins))
+    app.router.add_get(f'{prefix}/api/plugin-pages', panel_auth(list_plugin_web_pages))
     app.router.add_post(f'{prefix}/api/plugins/{{name}}/{{action}}', panel_auth(manage_plugin))
     app.router.add_get(f'{prefix}/api/plugins/{{name}}/perms', panel_auth(get_perms))
     app.router.add_post(f'{prefix}/api/plugins/{{name}}/perms', panel_auth(set_perms))
@@ -54,6 +55,26 @@ async def manage_plugin(req):
         logger.error(f"插件操作失败: {e}")
         return web.json_response({"success": False, "error": str(e)})
 
+async def list_plugin_web_pages(req):
+    """Return all registered plugin web UI pages for sidebar listing."""
+    sm = req.app.get('service_manager')
+    if not sm:
+        return web.json_response({"pages": []})
+    ps = sm.get_service("plugin")
+    if not ps:
+        return web.json_response({"pages": []})
+    pages = []
+    for name, plugin in ps.plugins.items():
+        if hasattr(plugin, "get_web_pages"):
+            for path, info in plugin.get_web_pages().items():
+                pages.append({
+                    "plugin": name,
+                    "path": "/plugin/" + name,
+                    "title": info.get("title", name),
+                    "icon": info.get("icon", "P"),
+                })
+    return web.json_response({"pages": pages})
+
 async def get_perms(req):
     return web.json_response({"plugin": req.match_info['name'], "permissions": ["read", "write"]})