RDoc-3779 + RDoc-3848 Control order of NULLs in query results

[Danielle9897]

Issue link

https://issues.hibernatingrhinos.com/issue/RDoc-3779/Corax-Configurable-order-of-NULLs-when-sorting
https://issues.hibernatingrhinos.com/issue/RDoc-3848/Corax-Control-order-of-NULLs-directly-in-query
https://issues.hibernatingrhinos.com/issue/RDoc-3858/Sort-query-results-Add-performance-notes-Metadata-example

Additional description

Updated articles:

• Indexing configuration (docs/server/configuration/indexing-configuration.mdx)
  • Indexing.Querying.Corax.NullFirst
  • Indexing.Querying.Corax.NullsSortMode
• RQL (docs/querying/rql/what-is-rql.mdx)
  • New syntax for ORDER BY
• Sort query results (docs/querying/sorting-query-results/content/_sort-query-results-csharp.mdx)
  • New sections:
    • "Control position of null values" + add info in "Chain ordering" (C# only)
    • "Order by metadata" (for RDoc-3858)
    • "Performance notes" (for RDoc-3858)
  • Enhance section:
    • "Force ordering type" (for RDoc-3858)
• Spatial query article (docs/client-api/session/querying/content/_how-to-make-a-spatial-query-csharp.mdx)
  • New overloads to OrderByDistance & OrderByDistanceDescending + add an example (C# only)

Type of change

• Content - docs
• Content - cloud
• Content - guides
• Content - start pages/other
• New docs feature (consider updating /templates or readme)
• Bug fix
• Optimization
• Other

Changes in docs URLs

• No changes in docs URLs
• Articles are restructured, URLs will change, mapping is required (update /scripts/redirects.json file, set Documents Moved PR label)

Changes in UX/UI

• No changes in UX/UI
• Changes in UX/UI (include screenshots and description)