feat: add --version flag to the CLI

- Add a `--version` flag to the main CLI group using click's `version_option`
- Prints `Scrapling, version <version>` and exits, sourcing the version from `scrapling.__version__`
- Add a CLI test asserting the flag's output

Closes #299

tests/cli/test_cli.py

@@ -4,8 +4,9 @@ from unittest.mock import patch, MagicMock
 import pytest_httpbin
 
 from scrapling.parser import Selector
+from scrapling import __version__
 from scrapling.cli import (
-    shell, mcp, get, post, put, delete, fetch, stealthy_fetch
+    main, shell, mcp, get, post, put, delete, fetch, stealthy_fetch
 )
 
 
@@ -32,6 +33,12 @@ class TestCLI:
     def runner(self):
         return CliRunner()
 
+    def test_version_flag(self, runner):
+        """Test that the --version flag prints the Scrapling version and exits"""
+        result = runner.invoke(main, ['--version'])
+        assert result.exit_code == 0
+        assert result.output.strip() == f'Scrapling, version {__version__}'
+
     def test_shell_command(self, runner):
         """Test shell command"""
         with patch('scrapling.core.shell.CustomShell') as mock_shell: