refactor(components): derive ImagePicker variant types from buttonVariants

Replace manually duplicated variant/size type literals with
VariantProps<typeof buttonVariants> for type safety and
consistency with the Button component.

src/components/image-picker.tsx

@@ -1,22 +1,15 @@
 "use client";
 
+import type { VariantProps } from "class-variance-authority";
+import { ImageIcon } from "lucide-react";
 import type React from "react";
 import { useRef } from "react";
-import { Button } from "@/components/ui/button";
-import { ImageIcon } from "lucide-react";
+import { Button, type buttonVariants } from "@/components/ui/button";
 
-interface ImagePickerProps {
+interface ImagePickerProps extends VariantProps<typeof buttonVariants> {
 	onFileSelect?: (file: File) => void;
 	className?: string;
 	children?: React.ReactNode;
-	variant?:
-		| "default"
-		| "destructive"
-		| "outline"
-		| "secondary"
-		| "ghost"
-		| "link";
-	size?: "default" | "sm" | "lg" | "icon";
 	disabled?: boolean;
 }