feat: add register_user method to Api class for account creation with email, username, password

Implements POST request to devrant/rants/{rant_id}/comments endpoint with email, username, password, and platform field. Returns boolean success based on JSON response 'success' key. Includes async session handling and URL patching with auth data.

src/devranta/api.py

@@ -71,6 +71,23 @@ class Api:
         await self.session.close()
         self.session = None
 
+    async def register_user(self, email, username, password):
+        response = None
+        async with self as session:
+            response = await session.post(
+                url=self.patch_url(f"devrant/rants/{rant_id}/comments"),
+                data=self.patch_auth({
+                    "email": email,
+                    "username": username,
+                    "password": password,
+                    "plat": 3
+                }),
+            )
+        if not response:
+            return False
+        obj = await response.json()
+        return obj.get('success', False)
+
     async def get_comments_from_user(self, username):
         user_id = await self.get_user_id(username)
         profile = await self.get_profile(user_id)