Add first class support to Wikidata in the backend

[HarelM]

• It adds a Wikidata source (that will replace the he and en wikipedia sources in the future).
• It allows adding links to Wikidata from the POI edit window.
• It merges between Wikidata and Wikipedia, and between OSM and Wikidata
• It merges iNature links as well (ref:IL:inature) as part of the merge algorithm
• It removes the updates and track of deleted POIs (in continue to #1979 )
• Resolves #2007

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Codecov Report

Attention: Patch coverage is 92.50000% with 9 lines in your changes missing coverage. Please review.

Project coverage is 90.46%. Comparing base (36c817b) to head (a1b30db).

Files with missing lines	Patch %	Lines
...sraelHiking.API/Executors/FeaturesMergeExecutor.cs	91.66%	4 Missing and 2 partials :warning:
...iking.API/Services/Poi/PointsOfInterestProvider.cs	91.30%	0 Missing and 2 partials :warning:
...PI/Services/Poi/WikidataPointsOfInterestAdapter.cs	94.73%	1 Missing :warning:

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Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #2075 +/- ## ========================================== + Coverage 90.43% 90.46% +0.03% ========================================== Files 100 101 +1 Lines 8520 8572 +52 Branches 1070 1074 +4 ========================================== + Hits 7705 7755 +50 - Misses 586 589 +3 + Partials 229 228 -1 ```

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