Using uppercase "PLUGINS" env variable instead of lowercase one. Fixes yGuy#48

Author: yGuy

src/plugins/GraphPlugin.ts

@@ -34,8 +34,9 @@ export class GraphPlugin extends PluginBase<GraphPluginArgs> {
     setup(): boolean {
         this.addPluginArgument('graphPrompt', 'string', 'A description or topic of the graph. This may also includes style, layout or edge properties')
 
-        if(!process.env.plugins || process.env.plugins.indexOf('graph-plugin') === -1)
-            return false
+        const plugins = process.env["PLUGINS"];
+        if(!plugins || plugins.indexOf('graph-plugin') === -1)
+          return false
 
         return !!this.yFilesGPTServerUrl
     }

src/plugins/ImagePlugin.ts

@@ -23,7 +23,8 @@ export class ImagePlugin extends PluginBase<ImagePluginArgs> {
     setup(): boolean {
         this.addPluginArgument('imageDescription', 'string', 'The description of the image provided by the user')
 
-        if(!process.env.plugins || process.env.plugins.indexOf('image-plugin') === -1)
+        const plugins = process.env["PLUGINS"];
+        if(!plugins || plugins.indexOf('image-plugin') === -1)
             return false
 
         return super.setup();