feat: replace Telegram bot with Discord bot

[Copilot]

Migrates the bot platform from Telegram (python-telegram-bot) to Discord (discord.py==2.4.0). All commands, interactive flows, and periodic notifications are preserved with equivalent Discord-native patterns.

Core Changes

• requirements.txt — swap python-telegram-bot==22.6 → discord.py==2.4.0
• topology_template.json — telegram_bot_token → discord_bot_token; admin ID is now a Discord snowflake
• config.py — drop Telegram ConversationHandler state integers (no longer needed)

Bot Architecture

• main.py — introduces RobbiBot(commands.Bot); shared state (node address, balance history, credentials, etc.) stored as instance attributes instead of application.bot_data; slash commands registered in setup_hook() + tree.sync()
• handlers/common.py — auth_required wraps discord.Interaction; reads whitelist from interaction.client.allowed_user_ids; handle_api_error uses interaction.followup.send()

Handler Rewrites

• handlers/node.py — ConversationHandler + inline keyboard callbacks replaced by discord.ui.View subclasses for multi-step confirmation flows and discord.ui.Modal for roll count input; setup_node_commands(bot) registers /node, /flush, /hist, /docker
• handlers/price.py — setup_price_commands(bot) registers /btc, /mas using defer + followup pattern
• handlers/system.py — setup_system_commands(bot) registers /hi, /temperature, /perf
• handlers/scheduler.py — periodic pings DM users via bot.fetch_user(user_id) instead of application.bot.send_message(chat_id=…)

Example: interactive docker menu flow

# Before (Telegram ConversationHandler + CallbackQueryHandler)
docker_handler = ConversationHandler(
    entry_points=[CommandHandler('docker', docker)],
    states={DOCKER_MENU_STATE: [CallbackQueryHandler(docker_start, pattern='^docker_start$'), ...]},
    ...
)

# After (Discord slash command + View)
@bot.tree.command(name='docker')
@auth_required
async def docker(interaction: discord.Interaction) -> None:
    await interaction.response.send_message(
        "🐳 Docker Node Management\nWhat do you want to do?",
        view=DockerMenuView(interaction.client)
    )

Original prompt

Je veux remplacer le bot Telegram par un bot discord.

Custom agent used: T800
Code maintainer and reviewer that develop the best application possible.

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