fix: sidebar menu visibility, model selector cleanup, time format

- Sidebar: restore DropdownMenu for session actions, fix long titles
  pushing button off-screen (add w-0 flex-1, w-full on content div)
- Model selector: remove SiliconFlow models, DeepSeek only
  (deepseek-reasoner default, deepseek-chat alternative)
- Message timestamp: change from HH:mm to yyyy/M/d HH:mm format
- Default model changed to deepseek-reasoner

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

web/src/components/chat/model-selector.tsx

@@ -8,10 +8,9 @@ import {
   DropdownMenuItem,
   DropdownMenuTrigger,
   DropdownMenuSeparator,
-  DropdownMenuLabel,
 } from "@/components/ui/dropdown-menu";
 import { Badge } from "@/components/ui/badge";
-import { ChevronDown, Cpu, Zap, Sparkles, Brain } from "lucide-react";
+import { ChevronDown, Cpu, Sparkles, Brain } from "lucide-react";
 import { cn } from "@/lib/utils";
 
 export interface ModelOption {
@@ -29,55 +28,25 @@ interface ModelSelectorProps {
   className?: string;
 }
 
-const modelGroups = [
+const models: ModelOption[] = [
   {
+    id: "deepseek-reasoner",
+    name: "DeepSeek-R1",
+    description: "深度推理模型，适合复杂分析任务",
     provider: "deepseek-official",
-    label: "DeepSeek 官方",
-    models: [
-      {
-        id: "deepseek-chat",
-        name: "DeepSeek-V3",
-        description: "DeepSeek 最新通用模型，速度快、能力强",
-        provider: "deepseek-official",
-        providerLabel: "DeepSeek",
-        icon: Sparkles,
-      },
-      {
-        id: "deepseek-reasoner",
-        name: "DeepSeek-R1",
-        description: "深度推理模型，适合复杂分析任务",
-        provider: "deepseek-official",
-        providerLabel: "DeepSeek",
-        icon: Brain,
-      },
-    ],
+    providerLabel: "DeepSeek",
+    icon: Brain,
   },
   {
-    provider: "siliconflow",
-    label: "SiliconFlow（硅基流动）",
-    models: [
-      {
-        id: "deepseek-ai/DeepSeek-V3",
-        name: "DeepSeek-V3",
-        description: "通过硅基流动调用，稳定的推理能力",
-        provider: "siliconflow",
-        providerLabel: "硅基流动",
-        icon: Sparkles,
-      },
-      {
-        id: "Qwen/QwQ-32B",
-        name: "QwQ-32B",
-        description: "Qwen 推理模型，高效准确",
-        provider: "siliconflow",
-        providerLabel: "硅基流动",
-        icon: Zap,
-      },
-    ],
+    id: "deepseek-chat",
+    name: "DeepSeek-V3",
+    description: "通用模型，速度快、能力强",
+    provider: "deepseek-official",
+    providerLabel: "DeepSeek",
+    icon: Sparkles,
   },
 ];
 
-const allModels = modelGroups.flatMap((g) => g.models);
-
 export default function ModelSelector({
   selectedModel,
   onModelChange,
@@ -86,7 +55,7 @@ export default function ModelSelector({
   const [isOpen, setIsOpen] = useState(false);
 
   const selectedModelData =
-    allModels.find((model) => model.id === selectedModel) || allModels[0];
+    models.find((model) => model.id === selectedModel) || models[0];
   const IconComponent = selectedModelData.icon || Cpu;
 
   return (
@@ -107,51 +76,44 @@ export default function ModelSelector({
           <ChevronDown className="w-3 h-3 ml-1 opacity-50" />
         </Button>
       </DropdownMenuTrigger>
-      <DropdownMenuContent align="start" className="w-72">
+      <DropdownMenuContent align="start" className="w-64">
         <div className="px-2 py-1.5 text-xs font-medium text-muted-foreground">
           选择AI模型
         </div>
         <DropdownMenuSeparator />
-        {modelGroups.map((group) => (
-          <div key={group.provider}>
-            <DropdownMenuLabel className="text-xs text-muted-foreground/70 font-normal px-2 pt-2">
-              {group.label}
-            </DropdownMenuLabel>
-            {group.models.map((model) => {
-              const ModelIcon = model.icon || Cpu;
-              const isSelected = model.id === selectedModel;
+        {models.map((model) => {
+          const ModelIcon = model.icon || Cpu;
+          const isSelected = model.id === selectedModel;
 
-              return (
-                <DropdownMenuItem
-                  key={model.id}
-                  onClick={() => {
-                    onModelChange(model.id);
-                    setIsOpen(false);
-                  }}
-                  className={cn(
-                    "flex items-start space-x-3 p-3 cursor-pointer",
-                    isSelected && "bg-muted/50"
+          return (
+            <DropdownMenuItem
+              key={model.id}
+              onClick={() => {
+                onModelChange(model.id);
+                setIsOpen(false);
+              }}
+              className={cn(
+                "flex items-start space-x-3 p-3 cursor-pointer",
+                isSelected && "bg-muted/50"
+              )}
+            >
+              <ModelIcon className="w-4 h-4 mt-0.5 flex-shrink-0" />
+              <div className="flex-1 min-w-0">
+                <div className="flex items-center space-x-2">
+                  <span className="font-medium text-sm">{model.name}</span>
+                  {isSelected && (
+                    <Badge variant="secondary" className="text-xs">
+                      已选择
+                    </Badge>
                   )}
-                >
-                  <ModelIcon className="w-4 h-4 mt-0.5 flex-shrink-0" />
-                  <div className="flex-1 min-w-0">
-                    <div className="flex items-center space-x-2">
-                      <span className="font-medium text-sm">{model.name}</span>
-                      {isSelected && (
-                        <Badge variant="secondary" className="text-xs">
-                          已选择
-                        </Badge>
-                      )}
-                    </div>
-                    <p className="text-xs text-muted-foreground mt-0.5">
-                      {model.description}
-                    </p>
-                  </div>
-                </DropdownMenuItem>
-              );
-            })}
-          </div>
-        ))}
+                </div>
+                <p className="text-xs text-muted-foreground mt-0.5">
+                  {model.description}
+                </p>
+              </div>
+            </DropdownMenuItem>
+          );
+        })}
       </DropdownMenuContent>
     </DropdownMenu>
   );