Reorganize repository into monorepo structure

Restructured the project to support multiple frontend applications:
- Move web app to web/ directory
- Create pezkuwi-sdk-ui/ for Polkadot SDK clone (planned)
- Create mobile/ directory for mobile app development
- Add shared/ directory with common utilities, types, and blockchain code
- Update README.md with comprehensive documentation
- Remove obsolete DKSweb/ directory

This monorepo structure enables better code sharing and organized
development across web, mobile, and SDK UI projects.

web/src/components/ui/radio-group.tsx

@@ -0,0 +1,42 @@
+import * as React from "react"
+import * as RadioGroupPrimitive from "@radix-ui/react-radio-group"
+import { Circle } from "lucide-react"
+
+import { cn } from "@/lib/utils"
+
+const RadioGroup = React.forwardRef<
+  React.ElementRef<typeof RadioGroupPrimitive.Root>,
+  React.ComponentPropsWithoutRef<typeof RadioGroupPrimitive.Root>
+>(({ className, ...props }, ref) => {
+  return (
+    <RadioGroupPrimitive.Root
+      className={cn("grid gap-2", className)}
+      {...props}
+      ref={ref}
+    />
+  )
+})
+RadioGroup.displayName = RadioGroupPrimitive.Root.displayName
+
+const RadioGroupItem = React.forwardRef<
+  React.ElementRef<typeof RadioGroupPrimitive.Item>,
+  React.ComponentPropsWithoutRef<typeof RadioGroupPrimitive.Item>
+>(({ className, ...props }, ref) => {
+  return (
+    <RadioGroupPrimitive.Item
+      ref={ref}
+      className={cn(
+        "aspect-square h-4 w-4 rounded-full border border-primary/60 text-primary ring-offset-background focus:outline-none focus-visible:ring-2 focus-visible:ring-primary focus-visible:ring-offset-2 disabled:cursor-not-allowed disabled:opacity-50 transition-all duration-200",
+        className
+      )}
+      {...props}
+    >
+      <RadioGroupPrimitive.Indicator className="flex items-center justify-center">
+        <Circle className="h-2.5 w-2.5 fill-current text-current animate-in scale-in-0 duration-200" />
+      </RadioGroupPrimitive.Indicator>
+    </RadioGroupPrimitive.Item>
+  )
+})
+RadioGroupItem.displayName = RadioGroupPrimitive.Item.displayName
+
+export { RadioGroup, RadioGroupItem }