feat(backend): add tool version check command

Add get_tool_versions command to check local and latest versions of
Claude, Codex, and Gemini CLI tools:

- Detect local installed versions via command line execution
- Fetch latest versions from npm registry (Claude, Gemini)
  and GitHub releases API (Codex)
- Return comprehensive version info including error details
  for uninstalled tools
- Register command in Tauri invoke handler

src/components/ui/accordion.tsx

@@ -0,0 +1,56 @@
+import * as React from "react"
+import * as AccordionPrimitive from "@radix-ui/react-accordion"
+import { ChevronDown } from "lucide-react"
+
+import { cn } from "@/lib/utils"
+
+const Accordion = AccordionPrimitive.Root
+
+const AccordionItem = React.forwardRef<
+    React.ElementRef<typeof AccordionPrimitive.Item>,
+    React.ComponentPropsWithoutRef<typeof AccordionPrimitive.Item>
+>(({ className, ...props }, ref) => (
+    <AccordionPrimitive.Item
+        ref={ref}
+        className={cn("border-b", className)}
+        {...props}
+    />
+))
+AccordionItem.displayName = "AccordionItem"
+
+const AccordionTrigger = React.forwardRef<
+    React.ElementRef<typeof AccordionPrimitive.Trigger>,
+    React.ComponentPropsWithoutRef<typeof AccordionPrimitive.Trigger>
+>(({ className, children, ...props }, ref) => (
+    <AccordionPrimitive.Header className="flex">
+        <AccordionPrimitive.Trigger
+            ref={ref}
+            className={cn(
+                "flex flex-1 items-center justify-between py-4 font-medium transition-all hover:underline [&[data-state=open]>svg]:rotate-180",
+                className
+            )}
+            {...props}
+        >
+            {children}
+            <ChevronDown className="h-4 w-4 shrink-0 transition-transform duration-200" />
+        </AccordionPrimitive.Trigger>
+    </AccordionPrimitive.Header>
+))
+AccordionTrigger.displayName = AccordionPrimitive.Trigger.displayName
+
+const AccordionContent = React.forwardRef<
+    React.ElementRef<typeof AccordionPrimitive.Content>,
+    React.ComponentPropsWithoutRef<typeof AccordionPrimitive.Content>
+>(({ className, children, ...props }, ref) => (
+    <AccordionPrimitive.Content
+        ref={ref}
+        className="overflow-hidden text-sm transition-all data-[state=closed]:animate-accordion-up data-[state=open]:animate-accordion-down"
+        {...props}
+    >
+        <div className={cn("pb-4 pt-0", className)}>{children}</div>
+    </AccordionPrimitive.Content>
+))
+
+AccordionContent.displayName = AccordionPrimitive.Content.displayName
+
+export { Accordion, AccordionItem, AccordionTrigger, AccordionContent }