Provide TypeScript typings for dnsconfig.js (#1830)

Co-authored-by: Jeffrey Cafferata <jeffrey@jcid.nl>
Co-authored-by: Tom Limoncelli <tlimoncelli@stackoverflow.com>

build/generate/dtsFile.go

@@ -0,0 +1,28 @@
+package main
+
+import (
+	"os"
+	"strings"
+)
+
+func generateDTSFile(funcs string) error {
+	names := []string{
+		"base-types",
+		"fetch",
+		"others",
+	}
+
+	combined := []string{
+		"// WARNING: These type definitions are experimental and subject to change in future releases.",
+	}
+	for _, name := range names {
+		content, err := os.ReadFile(join("types", "src", name+".d.ts"))
+		if err != nil {
+			return err
+		}
+		combined = append(combined, string(content))
+	}
+	combined = append(combined, funcs)
+	os.WriteFile(join("types", "dnscontrol.d.ts"), []byte(strings.Join(combined, "\n\n")), 0644)
+	return nil
+}