refactor(web): router-based navigation, light theme, form config

- Replace Zustand activeView with React Router (NavLink + Routes)
- White/light modern theme with indigo accents
- Sidebar with Chinese labels under icons
- ConfigForm with individual form fields (no JSON textareas)
- Account switching with context injection into chat
- Fix duplicate conversation creation with useRef guard
- Asset gallery: smaller 6-column grid with date labels
- All components updated to light color scheme

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

web/client/src/components/prompts/PromptEditor.tsx

@@ -35,7 +35,7 @@ export function PromptEditor() {
           <select
             value={selectedAccount}
             onChange={(e) => setSelectedAccount(e.target.value)}
-            className="mt-1 w-full h-9 rounded-md border border-zinc-800 bg-zinc-900 px-2 text-sm"
+            className="mt-1 w-full h-9 rounded-md border border-zinc-200 bg-zinc-50 px-2 text-sm"
           >
             {accounts.map((a) => (
               <option key={a.id} value={a.id}>{a.name}</option>
@@ -50,7 +50,7 @@ export function PromptEditor() {
                 key={type}
                 onClick={() => setSelectedType(type)}
                 className={`w-full text-left px-2 py-1.5 rounded text-sm ${
-                  selectedType === type ? 'bg-zinc-800 text-white' : 'text-zinc-500 hover:text-zinc-300'
+                  selectedType === type ? 'bg-indigo-50 text-indigo-700 font-medium' : 'text-zinc-500 hover:text-zinc-700 hover:bg-zinc-50'
                 }`}
               >
                 {label}
@@ -74,7 +74,7 @@ export function PromptEditor() {
         <textarea
           value={content}
           onChange={(e) => setContent(e.target.value)}
-          className="flex-1 w-full bg-zinc-950 text-zinc-200 font-mono text-sm p-4 resize-none outline-none"
+          className="flex-1 w-full bg-white text-zinc-700 font-mono text-sm p-4 resize-none outline-none"
           placeholder="加载中..."
           spellCheck={false}
         />