feat(withdraw): add user withdrawal flow using CryptoPay

keyboards/user.py

@@ -19,6 +19,17 @@ def main_menu_kb() -> InlineKeyboardMarkup:
     )
 
 
+def activate_kb(url: str, amount: float) -> InlineKeyboardMarkup:
+    if not url:
+        return back_kb()
+
+    return InlineKeyboardMarkup(
+        inline_keyboard=[
+            [InlineKeyboardButton(text=f"Получить {amount:.2f} ₽", url=url)]
+        ]
+    )
+
+
 def back_kb(callback_data: str = "back_main") -> InlineKeyboardMarkup:
     return InlineKeyboardMarkup(
         inline_keyboard=[