Add `warn` log level

data/core/init.lua

@@ -1089,6 +1089,9 @@ function core.log_quiet(...)
   return log("INFO", false, false, ...)
 end
 
+function core.warn(...)
+  return log("WARN", true, true, ...)
+end
 
 function core.error(...)
   return log("ERROR", true, true, ...)

data/core/style.lua

@@ -76,6 +76,7 @@ style.syntax_fonts = {}
 
 style.log = {
   INFO  = { icon = "i", color = style.text },
+  WARN  = { icon = "!", color = style.warn },
   ERROR = { icon = "!", color = style.error }
 }