fix(imports/locale): prevent error from invalid locales

People with poorly formatted json files would not get a locales table,
leading to an error when trying to iterate.
Contains some other inconsequential changes, and warnings.

imports/locale/shared.lua

@@ -1,29 +1,45 @@
+---@type { [string]: string }
 local dict = {}
 
 ---@param str string
 ---@param ... string | number
 ---@return string
 function locale(str, ...)
-	local lstr = dict[str]
+    local lstr = dict[str]
 
-	if lstr then
+    if lstr then
-		if ... then
+        if ... then
-			return lstr and lstr:format(...)
+            return lstr and lstr:format(...)
-		end
+        end
 
-		return lstr
+        return lstr
-	end
+    end
 
-	return str
+    return str
 end
 
----@return { [string]: string }
 function lib.getLocales()
     return dict
 end
 
-function lib.loadLocale()
+function lib.locale()
-	local locales = json.decode(LoadResourceFile(cache.resource, ('locales/%s.json'):format(GetConvar('ox:locale', 'en'))) or LoadResourceFile(cache.resource, 'locales/en.json') or '[]')
+    local lang = GetConvar('ox:locale', 'en')
+    local locales = json.decode(LoadResourceFile(cache.resource, ('locales/%s.json'):format(lang)))
+
+    if not locales then
+        local warning = "could not load 'locales/%s.json'"
+        warn(warning:format(lang))
+
+        if lang ~= 'en' then
+            locales = json.decode(LoadResourceFile(cache.resource, 'locales/en.json'))
+
+            if not locales then
+                warn(warning:format('en'))
+            end
+        end
+
+        if not locales then return end
+    end
 
     for k, v in pairs(locales) do
         if type(v) == 'string' then
@@ -41,4 +57,4 @@ function lib.loadLocale()
     end
 end
 
-return lib.loadLocale
+return lib.locale