feat: add MTR display board and train info components

- Implemented MtrDisplayBoard component to show train schedules with weather information.
- Created MtrTrainInfo component to manage state and render MtrDisplayBoard.
- Added ScreenshotTaker component for downloading screenshots of the display board.
- Introduced theme toggle functionality with ThemeToggle component.
- Developed various UI components including Button, Card, ColorPicker, DropdownMenu, Input, Label, Popover, Select, Separator, Switch, Tabs, and Textarea.
- Added utility functions for class name merging and tool definitions.

src/lib/tools.ts

@@ -0,0 +1,23 @@
+export interface Tool {
+  title: string;
+  description: string;
+  href: string;
+}
+
+export const tools: Tool[] = [
+  {
+    title: "Rail Transit Guide",
+    description: "轨道交通导视生成器",
+    href: "/rt-guide",
+  },
+  {
+    title: "URL Encoder/Decoder",
+    description: "Encode or decode URLs and strings.",
+    href: "/url-encoder",
+  },
+  {
+    title: "Base64 Encoder/Decoder",
+    description: "Encode or decode strings to and from Base64.",
+    href: "/base64-encoder",
+  },
+];