Add grip dots visual indicator to splitter bar

- ::after pseudo-element with radial-gradient dot pattern
- Dots darken on hover/active for contrast against accent background
- Bump 1.22.14, SW cache v45->v46

tests/test_pcap_import.py

@@ -224,7 +224,7 @@ class TestImportEndpoint(unittest.TestCase):
 class TestVersion(unittest.TestCase):
     def test_package_version(self):
         from simtrace2_pysniff import __version__
-        self.assertEqual(__version__, '1.22.13')
+        self.assertEqual(__version__, '1.22.14')
 
     def test_status_includes_version(self):
         import os