According to the logs of the recent test failure, there's a small window when we test the connection is established where we have a socket connected but don't have the session created yet, and this is throwing exception when trying to disconnect because the renew loop is not yet created.

This is caused by the HaManager (in charge of connecting/reconnecting the clients) running in its own task, thus we're not in the usual await connect(); await disconnect() scenario.
This can also arguably be fixed at the client level by checking if
the renew loop exist on disconnect.

The HaClient is missing from the PyPi package:

```
[/tmp]> curl https://codeload.github.com/FreeOpcUa/opcua-asyncio/tar.gz/refs/tags/v0.9.91 -s -o v0.9.91.tar.gz
[/tmp]> tar xvf v0.9.91.tar.gz > /dev/null 2>&1
[/tmp]> cd opcua-asyncio-0.9.91/
[/tmp/opcua-asyncio-0.9.91]> python setup.py install > /dev/null 2>&1
[/tmp/opcua-asyncio-0.9.91]> find build/ -type f |grep -i ha
build//lib/tests/test_ha_client.py
build//lib/asyncua/ua/uaprotocol_hand.py
```

The build rules only look for the packages via
(`find_packages`) in setup.py, making the ha client sub-directory a
package fixes it:
```
[/tmp/opcua-asyncio-0.9.91]> rm -rf build/
[/tmp/opcua-asyncio-0.9.91]> cat asyncua/client/ha/__init__.py
"""
Pure Python OPC-UA library
"""

from .ha_client import HaClient, HaMode, HaSecurityConfig, ConnectionStatesing
[/tmp/opcua-asyncio-0.9.91]> python setup.py build > /dev/null 2>&1
[/tmp/opcua-asyncio-0.9.91]> find build/ -type f |grep -i ha
build//lib/tests/test_ha_client.py
build//lib/asyncua/ua/uaprotocol_hand.py
build//lib/asyncua/client/ha/__init__.py
build//lib/asyncua/client/ha/common.py
build//lib/asyncua/client/ha/ha_client.py
build//lib/asyncua/client/ha/reconciliator.py
build//lib/asyncua/client/ha/virtual_subscription.py
```

Changing the HaClient test import path to ensure no regression.

Avoid running introspection code every time a message is deserialized

See https://github.com/FreeOpcUa/opcua-asyncio/pull/700

* Reduction of network access

Cache the nodes of potentially multiple-used FileType methods.

* indentation error corrected

* Add low-level file system functionality

* Added examples for the use of ua_file_transfer.py

In the following you will find examples for the use of the
classes UaFile and UaDirectory and how to handle typical uaerrors.
see: ./asyncua/client/ua_file_transfer.py.

The OPC UA File Transfer specification can be found here:
https://reference.opcfoundation.org/Core/docs/Part5/C.1/

* pylint optimized - ua_file_transfer.py 

pylint optimization of file ua_file_transfer.py.
=> Your code has been rated at 10.00/10 (previous run: 10.00/10, +0.00)

* pylint optimized - client_ua_file_transfer.py

pylint optimization of client_ua_file_transfer.py.
=> Your code has been rated at 10.00/10 (previous run: 10.00/10, +0.00)
Co-authored-by: Curious Crook <privat@nowhere.org>

Augmented assignment statements became available with Python 2.
https://docs.python.org/3/whatsnew/2.0.html#augmented-assignment

Thus improve three source code places accordingly.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>

The test suite used to create files in the CWD, which then showed up as untracked files in git, and would cause the tests to fail when ran successively with different users.

This commit makes successive test runs independant from each other

* 3x performance improvement for serialization

Instead of re-inspecting the type metadata everytime an object is serialized,
create a single serialization function for each type and just call it when an instance is serialized

* pre-compute uatype array serializers

* Make VariantTypeCustom instances valid cache keys

VariantTypeCustom instances can be used as cache keys for serialization functions

* Enable the server to listen to an arbitrary IP

* Add missing doc
Co-authored-by: oroulet <oroulet@users.noreply.github.com>

With this change you can authenticate via user certificate over sync api.
The application-uri is required, because some servers will reject the connection if the application-uri of the application does not match the one from the client application certificate.

Allow using OptionSets from Addresspace und dynamic creation of OptionSets