refactor: put HTTP and XML logic into reusable modules

src/Utility/HttpClient.h

@@ -0,0 +1,16 @@
+#ifndef HTTPCLIENT_H
+#define HTTPCLIENT_H
+
+#include <curl/curl.h>
+#include <stddef.h>
+
+typedef struct {
+  char *memory;
+  size_t size;
+  size_t capacity;
+} HttpResponse;
+
+HttpResponse http_get(const char *url, const char *user_agent);
+void http_response_free(HttpResponse *resp);
+
+#endif