feat: migrate to golang

internal/corecfg/merge.go

@@ -0,0 +1,27 @@
+package corecfg
+
+// deepMerge merges dict2 into dict1 in place and returns dict1, mirroring
+// corecfg_manager.py's module-level deep_merge(): nested maps recurse,
+// matching lists are concatenated, everything else is overwritten by dict2.
+func deepMerge(dict1, dict2 map[string]interface{}) map[string]interface{} {
+	for k, v := range dict2 {
+		existing, exists := dict1[k]
+		if exists {
+			existingMap, existingIsMap := existing.(map[string]interface{})
+			vMap, vIsMap := v.(map[string]interface{})
+			if existingIsMap && vIsMap {
+				dict1[k] = deepMerge(existingMap, vMap)
+				continue
+			}
+
+			existingList, existingIsList := existing.([]interface{})
+			vList, vIsList := v.([]interface{})
+			if existingIsList && vIsList {
+				dict1[k] = append(existingList, vList...)
+				continue
+			}
+		}
+		dict1[k] = v
+	}
+	return dict1
+}