fix: missing errors content type

app/lib/errors.cr

@@ -3,6 +3,7 @@ require "kemal"
 module App
   class BadRequestException < Kemal::Exceptions::CustomException
     def initialize(context, message : String)
+      context.response.content_type = "application/json"
       context.response.status_code = 400
       context.response.print({ "error" => message }.to_json)
       super(context)
@@ -11,13 +12,16 @@ module App
 
   class UnauthorizedException < Kemal::Exceptions::CustomException
     def initialize(context)
+      context.response.content_type = "application/json"
       context.response.status_code = 401
+      context.response.print({ "error" => "Unauthorized access" }.to_json)
       super(context)
     end
   end
 
   class ForbiddenException < Kemal::Exceptions::CustomException
     def initialize(context)
+      context.response.content_type = "application/json"
       context.response.status_code = 403
       context.response.print({ "error" => "Access not allowed" }.to_json)
       super(context)
@@ -26,13 +30,16 @@ module App
 
   class NotFoundException < Kemal::Exceptions::CustomException
     def initialize(context)
+      context.response.content_type = "application/json"
       context.response.status_code = 404
+      context.response.print({ "error" => "Resource not found" }.to_json)
       super(context)
     end
   end
 
   class UnprocessableEntityException < Kemal::Exceptions::CustomException
     def initialize(context, message : Hash(String, Array(String)))
+      context.response.content_type = "application/json"
       context.response.status_code = 422
       context.response.print({ "errors" => message }.to_json)
       super(context)