[socket] Fix set_sockaddr() accepting malformed IPv4 addresses (#19394)

Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com>

tests/components/socket/__init__.py

@@ -0,0 +1,16 @@
+# This file's presence makes pytest treat this directory as a package named "socket",
+# shadowing the stdlib module -- no test_*.py (Python-level) tests can live here.
+# required for cpp unit testing.
+import esphome.codegen as cg
+from tests.testing_helpers import ComponentManifestOverride
+
+
+def override_manifest(manifest: ComponentManifestOverride) -> None:
+    manifest.enable_codegen()
+    real_to_code = manifest.to_code
+
+    async def to_code_testing(config):
+        await real_to_code(config)
+        cg.add_define("USE_NETWORK_IPV6", True)
+
+    manifest.to_code = to_code_testing