[refactor] typification of SearXNG / EngineResults

In [1] and [2] we discussed the need of a Result.results property and how we can
avoid unclear code.  This patch implements a class for the reslut-lists of
engines::

    searx.result_types.EngineResults

A simple example for the usage in engine development::

    from searx.result_types import EngineResults
    ...
    def response(resp) -> EngineResults:
        res = EngineResults()
        ...
        res.add( res.types.Answer(answer="lorem ipsum ..", url="https://example.org") )
        ...
        return res

[1] https://github.com/searxng/searxng/pull/4183#pullrequestreview-257400034
[2] https://github.com/searxng/searxng/pull/4183#issuecomment-2614301580
Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>

searx/engines/google.py

@@ -25,7 +25,7 @@ from searx.locales import language_tag, region_tag, get_official_locales
 from searx.network import get  # see https://github.com/searxng/searxng/issues/762
 from searx.exceptions import SearxEngineCaptchaException
 from searx.enginelib.traits import EngineTraits
-from searx.result_types import Answer
+from searx.result_types import EngineResults
 
 if TYPE_CHECKING:
     import logging
@@ -316,12 +316,12 @@ def _parse_data_images(dom):
     return data_image_map
 
 
-def response(resp):
+def response(resp) -> EngineResults:
     """Get response from google's search request"""
     # pylint: disable=too-many-branches, too-many-statements
     detect_google_sorry(resp)
 
-    results = []
+    results = EngineResults()
 
     # convert the text to dom
     dom = html.fromstring(resp.text)
@@ -332,7 +332,12 @@ def response(resp):
     for item in answer_list:
         for bubble in eval_xpath(item, './/div[@class="nnFGuf"]'):
             bubble.drop_tree()
-        Answer(results=results, answer=extract_text(item), url=(eval_xpath(item, '../..//a/@href') + [None])[0])
+        results.add(
+            results.types.Answer(
+                answer=extract_text(item),
+                url=(eval_xpath(item, '../..//a/@href') + [None])[0],
+            )
+        )
 
     # parse results