Mark system as unhealthy on OSError Bad message errors (#4750)

* Bad message error marks system as unhealthy

* Finish adding test cases for changes

* Rename test file for uniqueness

* bad_message to oserror_bad_message

* Omit some checks and check for network mounts

tests/plugins/test_audio.py

@@ -1,4 +1,5 @@
 """Test audio plugin."""
+import errno
 from pathlib import Path
 from unittest.mock import AsyncMock, Mock, patch
 
@@ -56,3 +57,26 @@ async def test_config_write(
             "debug": True,
         },
     )
+
+
+async def test_load_error(
+    coresys: CoreSys, caplog: pytest.LogCaptureFixture, container
+):
+    """Test error reading config file during load."""
+    with patch(
+        "supervisor.plugins.audio.Path.read_text", side_effect=(err := OSError())
+    ), patch("supervisor.plugins.audio.shutil.copy", side_effect=err):
+        err.errno = errno.EBUSY
+        await coresys.plugins.audio.load()
+
+        assert "Can't read pulse-client.tmpl" in caplog.text
+        assert "Can't create default asound" in caplog.text
+        assert coresys.core.healthy is True
+
+        caplog.clear()
+        err.errno = errno.EBADMSG
+        await coresys.plugins.audio.load()
+
+        assert "Can't read pulse-client.tmpl" in caplog.text
+        assert "Can't create default asound" in caplog.text
+        assert coresys.core.healthy is False