Automated snippet conversion by scripts

These changes are purely mechanical to differentiate them from manual
fixes/adjustments made in the next commit.
This results in broken code as some snippets contain errors.

Made in four steps:
1. Run ./migrate-snippet.py that converts `.md` files to code files
   and perhaps adds missing lines under `// @hide` comments.
2. Sort Java imports.
3. Remove old `.md` files.
4. Run ./generate.md to produce `*/generated/*.md` files.

qdrant-landing/content/documentation/headless/snippets/insert-points/with-condition/go.go

@@ -0,0 +1,31 @@
+package snippet
+
+import (
+    "context"
+
+    "github.com/qdrant/go-client/qdrant"
+)
+
+func Main() {
+	client, err := qdrant.NewClient(&qdrant.Config{
+	    Host: "localhost",
+	    Port: 6334,
+	})
+
+	client.Upsert(context.Background(), &qdrant.UpsertPoints{
+	    CollectionName: "{collection_name}",
+	    Points: []*qdrant.PointStruct{
+	        {
+	            Id:      qdrant.NewIDNum(1),
+	            Vectors: qdrant.NewVectors(0.05, 0.61, 0.76, 0.74),
+	            Payload: qdrant.NewValueMap(map[string]any{
+	                "city": "Berlin", "price": 1.99, "version": 3}),
+	        },
+	    },
+	    UpdateFilter: &qdrant.Filter{
+	        Must: []*qdrant.Condition{
+	            qdrant.NewMatchInt("version", 2),
+	        },
+	    },
+	})
+}