It took longer because the KDevelop API is complicated but now it is here, the KDevelop DragonScript Plugin (Linux).
Shows Declarations, Uses and Class Outlining information.
Supports Code Completion with generating function calls and code block calls.
Supports Code Generation for example easily overriding functions.
Get it here: Language Plugins.
More features will be added as time comes by.
Not into KDevelop or Linux? As an alternative there is also Plugin for Visual Studio Code. It has though less abilities right now.