fix: remove /start command and handle @botname suffix

Remove /start command as name doesn't match functionality, and fix
command parsing to handle @botname suffix for group chat compatibility.

Changes:
- Remove handle_start function and registration
- Remove /start from help command list
- Remove test_start_command_content test
- Strip @botname suffix from commands (e.g., /help@mybot → help)

Rationale:
- /start command name implies bot initialization, but it was just
  showing help text (duplicate of /help)
- Better to have one clear /help command
- @botname suffix handling needed for group chats

Test:
- 27 tests pass (1 removed, 1 added for @botname handling)
- All existing functionality preserved

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

src/main.py

@@ -579,25 +579,10 @@ async def run(settings: Settings) -> None:
     command_handler = TelegramCommandHandler(telegram)
 
     # Register basic commands
-    async def handle_start() -> None:
-        """Handle /start command."""
-        message = (
-            "<b>🤖 The Ouroboros Trading Bot</b>\n\n"
-            "AI-powered global stock trading agent with real-time notifications.\n\n"
-            "<b>Available commands:</b>\n"
-            "/help - Show this help message\n"
-            "/status - Current trading status\n"
-            "/positions - View holdings\n"
-            "/stop - Pause trading\n"
-            "/resume - Resume trading"
-        )
-        await telegram.send_message(message)
-
     async def handle_help() -> None:
         """Handle /help command."""
         message = (
             "<b>📖 Available Commands</b>\n\n"
-            "/start - Welcome message\n"
             "/help - Show available commands\n"
             "/status - Trading status (mode, markets, P&L)\n"
             "/positions - Current holdings\n"
@@ -722,7 +707,6 @@ async def run(settings: Settings) -> None:
                 "<b>⚠️ Error</b>\n\nFailed to retrieve positions."
             )
 
-    command_handler.register_command("start", handle_start)
     command_handler.register_command("help", handle_help)
     command_handler.register_command("stop", handle_stop)
     command_handler.register_command("resume", handle_resume)

src/notifications/telegram_client.py

@@ -492,7 +492,8 @@ class TelegramCommandHandler:
             if not command_parts:
                 return
 
-            command_name = command_parts[0]
+            # Remove @botname suffix if present (for group chats)
+            command_name = command_parts[0].split("@")[0]
 
             # Execute handler
             handler = self._commands.get(command_name)

tests/test_telegram_commands.py

@@ -230,6 +230,31 @@ class TestUpdateHandling:
         await handler._handle_update(update)
         assert executed is False
 
+    @pytest.mark.asyncio
+    async def test_handle_command_with_botname(self) -> None:
+        """Commands with @botname suffix are handled correctly."""
+        client = TelegramClient(bot_token="123:abc", chat_id="456", enabled=True)
+        handler = TelegramCommandHandler(client)
+
+        executed = False
+
+        async def test_command() -> None:
+            nonlocal executed
+            executed = True
+
+        handler.register_command("start", test_command)
+
+        update = {
+            "update_id": 1,
+            "message": {
+                "chat": {"id": 456},
+                "text": "/start@mybot",
+            },
+        }
+
+        await handler._handle_update(update)
+        assert executed is True
+
     @pytest.mark.asyncio
     async def test_handle_update_error_isolation(self) -> None:
         """Errors in handlers don't crash the system."""
@@ -638,51 +663,6 @@ class TestStatusCommands:
 class TestBasicCommands:
     """Test basic command implementations."""
 
-    @pytest.mark.asyncio
-    async def test_start_command_content(self) -> None:
-        """Start command contains welcome message and command list."""
-        client = TelegramClient(bot_token="123:abc", chat_id="456", enabled=True)
-        handler = TelegramCommandHandler(client)
-
-        mock_resp = AsyncMock()
-        mock_resp.status = 200
-        mock_resp.__aenter__ = AsyncMock(return_value=mock_resp)
-        mock_resp.__aexit__ = AsyncMock(return_value=False)
-
-        async def mock_start() -> None:
-            """Mock /start handler."""
-            message = (
-                "<b>🤖 The Ouroboros Trading Bot</b>\n\n"
-                "AI-powered global stock trading agent with real-time notifications.\n\n"
-                "<b>Available commands:</b>\n"
-                "/help - Show this help message\n"
-                "/status - Current trading status\n"
-                "/positions - View holdings\n"
-                "/stop - Pause trading\n"
-                "/resume - Resume trading"
-            )
-            await client.send_message(message)
-
-        handler.register_command("start", mock_start)
-
-        with patch("aiohttp.ClientSession.post", return_value=mock_resp) as mock_post:
-            update = {
-                "update_id": 1,
-                "message": {
-                    "chat": {"id": 456},
-                    "text": "/start",
-                },
-            }
-
-            await handler._handle_update(update)
-
-            # Verify message was sent
-            assert mock_post.call_count == 1
-            payload = mock_post.call_args.kwargs["json"]
-            assert "Ouroboros Trading Bot" in payload["text"]
-            assert "/help" in payload["text"]
-            assert "/status" in payload["text"]
-
     @pytest.mark.asyncio
     async def test_help_command_content(self) -> None:
         """Help command lists all available commands."""
@@ -698,7 +678,6 @@ class TestBasicCommands:
             """Mock /help handler."""
             message = (
                 "<b>📖 Available Commands</b>\n\n"
-                "/start - Welcome message\n"
                 "/help - Show available commands\n"
                 "/status - Trading status (mode, markets, P&L)\n"
                 "/positions - Current holdings\n"
@@ -724,7 +703,6 @@ class TestBasicCommands:
             assert mock_post.call_count == 1
             payload = mock_post.call_args.kwargs["json"]
             assert "Available Commands" in payload["text"]
-            assert "/start" in payload["text"]
             assert "/help" in payload["text"]
             assert "/status" in payload["text"]
             assert "/positions" in payload["text"]