fix(dashboard): eliminate middleware deprecation warning

- Rename middleware.ts → proxy.ts
- Update to use default proxy export (Next.js 16)

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dashboard/proxy.ts

@@ -6,7 +6,7 @@ function stripTrailingSlashes(pathname: string) {
   return pathname.replace(/\/+$/u, '')
 }
 
-export function middleware(request: NextRequest) {
+export default async function proxy(request: NextRequest) {
   const { pathname } = request.nextUrl
   const isApiRoute = pathname === '/api' || pathname.startsWith('/api/')
   const shouldStrip = isApiRoute && pathname.length > 1 && pathname.endsWith('/')

dashboard/src/extensions/builtin/user-center/routes/management.tsx

@@ -277,10 +277,8 @@ export default function UserCenterManagementRoute() {
         users={usersSWR.data}
         isLoading={usersLoading}
         onRoleChange={handleRoleChange}
-        onRoleReset={handleRoleReset}
         canEditRoles={canEditRoles}
         pendingUserIds={pendingRoleUpdates}
-        message={roleUpdateMessage}
       />
     </div>
   )

dashboard/ui/components/MarkdownSection.tsx

@@ -1,6 +1,7 @@
 'use client'
 
 import { useEffect, useMemo, useState, type ReactNode } from 'react'
+import type { JSX } from 'react'
 import clsx from 'clsx'
 
 import type { MarkdownRenderResult } from '../../api/render-markdown'