[mod] addition of various type hints / tbc

- pyright configuration [1]_
- stub files: types-lxml [2]_
- addition of various type hints
- enable use of new type system features on older Python versions [3]_
- ``.tool-versions`` - set python to lowest version we support (3.10.18) [4]_:
  Older versions typically lack some typing features found in newer Python
  versions.  Therefore, for local type checking (before commit), it is necessary
  to use the older Python interpreter.

.. [1] https://docs.basedpyright.com/v1.20.0/configuration/config-files/
.. [2] https://pypi.org/project/types-lxml/
.. [3] https://typing-extensions.readthedocs.io/en/latest/#
.. [4] https://mise.jdx.dev/configuration.html#tool-versions

Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>
Format: reST

searx/engines/google_scholar.py

@@ -7,9 +7,6 @@ can make use of the :ref:`google API` to assemble the arguments of the GET
 request.
 """
 
-from typing import TYPE_CHECKING
-from typing import Optional
-
 from urllib.parse import urlencode
 from datetime import datetime
 from lxml import html
@@ -28,14 +25,6 @@ from searx.engines.google import (
     get_google_info,
     time_range_dict,
 )
-from searx.enginelib.traits import EngineTraits
-
-if TYPE_CHECKING:
-    import logging
-
-    logger: logging.Logger
-
-traits: EngineTraits
 
 # about
 about = {
@@ -115,7 +104,7 @@ def request(query, params):
     return params
 
 
-def parse_gs_a(text: Optional[str]):
+def parse_gs_a(text: str | None):
     """Parse the text written in green.
 
     Possible formats: