Better color code detection

Should produce less false positives.

src/main.cpp

@@ -25,7 +25,7 @@ std::string remove_colors(const std::string &text)
     auto newtext{text};
 
     size_t pos{0};
-    while ((pos = newtext.find('\x1b')) != std::string::npos)
+    while ((pos = newtext.find("\x1b[")) != std::string::npos)
     {
         const auto nchars{newtext.find('m', pos) + 1 - pos};
         newtext.replace(pos, nchars, "");