how to use cogs and slash commands

I'm trying to use prefix commands together with slash commands, in cog files that are separated in a separate folder.

import os
import datetime
import asyncio
import random
from discord.ext import commands
from discord import app_commands
from dotenv import load_dotenv
import discloud

server_id = discord.Object(id=717615951113093130)
app_id = 1068876103009194025

hoje = datetime.datetime.today()
dia, mes, ano = hoje.day, hoje.month, hoje.year
hh, mm, ss = hoje.hour, hoje.minute, hoje.second

class MeuCliente(discord.Client):
    def __init__(self,*,intents:discord.Intents):
        super().__init__(
            application_id=app_id,
            command_prefix="!",
            intents=intents,
            )
        self.tree = app_commands.CommandTree(self)


    async def setup_hook(self):
        await self.load_extension("cogs.dashboard")
        await self.load_extension("cogs.embedcreator")

        self.tree.copy_global_to(guild=server_id)
        await self.tree.sync(guild=server_id) 

bot = MeuCliente(intents=discord.Intents.default())

@bot.event
async def on_ready():
    print(f"{bot.user.name} está online!")

load_dotenv()
TOKEN = os.getenv("DISCORD_TOKEN")

bot.run(TOKEN)

I want to be able to use both prefix commands and slash commands in cog files, but I can't implement a workaround for this error:

  File "f:\BotLand\Ticket 2\main.py", line 29, in setup_hook
    await self.load_extension("cogs.dashboard")
          ^^^^^^^^^^^^^^^^^^^
AttributeError: 'MeuCliente' object has no attribute 'load_extension'

A few days ago there was a similar question click me. I gave an easy explanation on how to setup a main file and a cog. Take a look at the main file. Maybe it helps you with the debugging. In this case it was about prefix commands. If you want to use slash commands you have to use the @app_commands decorator like this:

from discord import app_commands
@app_commands.command(name="blablabla", description='my first slash command')

Taking a closer look at your problem, I think you should try to implement your class like this:

class MeuCliente(commands.Bot):

Because in the discord.py documenation the "load_extensions" method is listed as a method of the commands.bot class, and not of the discord.client class.

Cogs are extensions to be loaded by an instance of commands.Bot. So your MeuCliente class needs to inherit commands.Bot. Also, commands.Bot already has its own tree, so you don't need to create a new one.

class MeuCliente(commands.Bot):
    def __init__(self):
        intents = discord.Intents.default()
        intents.message_content = True  # Isso é necessário para usar comandos de texto
        super().__init__(
            command_prefix="!",
            intents=intents,
        )


    async def setup_hook(self):
        await self.load_extension("cogs.dashboard")
        await self.load_extension("cogs.embedcreator")

        self.tree.copy_global_to(guild=server_id)
        await self.tree.sync(guild=server_id) 

bot = MeuCliente()

> Note: For your commands to work for both text and slash you need to define them using @hybrid_command decorator iside the cogs.