[wip] feat: add new implementation for wikidata and search endpoints

[Meminseeker]

This merge is required for frontend teams to use wikidata-suggestions and post-search endpoints.

• wikidata-suggestions: {{base_url}}:{{port}}/api/v1/users/wikidata-suggestions
• post-search: {{base_url}}:{{port}}/api/v1/users/post-search