feat(canvas): move object-pick action to bottom fixed toolbar

app/canvas/[id]/page.tsx

@@ -26,6 +26,7 @@ import {
   PenTool,
   Box,
   Layers,
+  Crosshair,
 } from "lucide-react";
 import { Button } from "@/components/ui/button";
 import { Input } from "@/components/ui/input";
@@ -122,6 +123,7 @@ export default function CanvasEditorPage({ params }: PageProps) {
   const selectNodes = useCanvasStore((state) => state.selectNodes);
   const updateNode = useCanvasStore((state) => state.updateNode);
   const setGenerating = useCanvasStore((state) => state.setGenerating);
+  const setPickerMode = useCanvasStore((state) => state.setPickerMode);
   
   // Local state
   const [isLoading, setIsLoading] = useState(true);
@@ -848,6 +850,30 @@ export default function CanvasEditorPage({ params }: PageProps) {
               <TooltipContent side="top">添加文本</TooltipContent>
             </Tooltip>
 
+            <Tooltip>
+              <TooltipTrigger asChild>
+                <Button
+                  variant="ghost"
+                  size="icon"
+                  disabled={!selectedImageNode}
+                  onClick={() => {
+                    if (!selectedImageNode) {
+                      toast.info("请先选中一张图片");
+                      return;
+                    }
+                    setPickerMode(true, selectedImageNode.id);
+                    toast.info("点击图片中的物品进行拾取");
+                  }}
+                  className="h-9 w-9 rounded-xl"
+                >
+                  <Crosshair className="h-4 w-4" />
+                </Button>
+              </TooltipTrigger>
+              <TooltipContent side="top">
+                {selectedImageNode ? "识物" : "先选中图片后识物"}
+              </TooltipContent>
+            </Tooltip>
+
             {siteSettingsData?.realtimeCanvasEnabled === true &&
             siteSettingsData?.realtimeCanvasServiceEnabled !== false ? (
               <Tooltip>

components/canvas/nodes/ImageNode.tsx

@@ -2199,13 +2199,6 @@ export function ImageNode({ node, isSelected }: ImageNodeProps) {
                   <RefreshCw className="mr-2 h-4 w-4" />
                   重绘
                 </DropdownMenuItem>
-                <DropdownMenuItem onClick={() => {
-                  setPickerMode(true, node.id);
-                  toast.info('点击图片中的物品进行拾取');
-                }}>
-                  <Crosshair className="mr-2 h-4 w-4" />
-                  拾物
-                </DropdownMenuItem>
                 <DropdownMenuItem onClick={() => handleAction('note')}>
                   <StickyNote className="mr-2 h-4 w-4" />
                   备注