Refactor Telegram bot and web application for improved functionality

- Disabled the default menu button in the Telegram bot, allowing users to access the app via a direct link.
- Updated the initData validation process to ensure URL-decoded values are used in the data-check string.
- Enhanced error handling in the web application to provide more informative access denial messages.
- Removed unnecessary debug information from the access denied section in the web app.
- Cleaned up the web application code by removing unused functions and improving CSS styles for hidden elements.

handlers/commands.py

@@ -1,9 +1,9 @@
-"""Command handlers: /start, /help; /start registers user and shows Calendar button."""
+"""Command handlers: /start, /help; /start registers user."""
 
 import asyncio
 
 import config
-from telegram import Update, WebAppInfo, InlineKeyboardButton, InlineKeyboardMarkup
+from telegram import Update
 from telegram.ext import CommandHandler, ContextTypes
 
 from db.session import get_session
@@ -42,27 +42,14 @@ async def start(update: Update, context: ContextTypes.DEFAULT_TYPE) -> None:
     await asyncio.get_running_loop().run_in_executor(None, do_get_or_create)
 
     text = "Привет! Я бот календаря дежурств. Используй /help для списка команд."
-    if config.MINI_APP_BASE_URL:
-        keyboard = InlineKeyboardMarkup(
-            [
-                [
-                    InlineKeyboardButton(
-                        "📅 Календарь",
-                        web_app=WebAppInfo(url=config.MINI_APP_BASE_URL + "/app/"),
-                    )
-                ],
-            ]
-        )
-        await update.message.reply_text(text, reply_markup=keyboard)
-    else:
-        await update.message.reply_text(text)
+    await update.message.reply_text(text)
 
 
 async def help_cmd(update: Update, context: ContextTypes.DEFAULT_TYPE) -> None:
     if update.message:
         await update.message.reply_text(
             "Доступные команды:\n"
-            "/start — Начать и открыть календарь\n"
+            "/start — Начать\n"
             "/help — Показать эту справку"
         )