docs: C# client usage - II (#607)

* docs: C# client usage guides

* docs: use named args

* Add files via upload

* docs: simplify explore.md list expressions

* docs: missed named args

* docs: csharp.svg

qdrant-landing/themes/qdrant/static/css/_lang-switcher.scss

@@ -66,6 +66,12 @@ $tabs-font-color-hover: var(--neutral-n-600);
         mask-image: url("/css/assets/lang-switcher/java.svg");
       }
     }
+    &_csharp {
+      &:before {
+        -webkit-mask-image: url("/css/assets/lang-switcher/csharp.svg");
+        mask-image: url("/css/assets/lang-switcher/csharp.svg");
+      }
+    }
 
     &:not(.active):hover {
       background: $tabs-bg-color-hover;

qdrant-landing/themes/qdrant/static/css/assets/lang-switcher/csharp.svg

@@ -0,0 +1 @@
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