Update logo, drop OpenAI completion, and update dependencies

Author: rw-access

.github/workflows/build-ext.yml

@@ -14,7 +14,7 @@ jobs:
       - name: Use Node.js
         uses: actions/setup-node@v4
         with:
-          node-version: "16.x"
+          node-version: "18.x"
 
       - name: Install dependencies
         run: npm ci

README.md

@@ -29,7 +29,6 @@ tags:
 The MQL extension for Visual Studio code provides validation and completion capabilities
 
 - Syntax highlighting
-- ChatGPT based completion for line comments (requires `openAIKey` in settings)
 - Autocompletion (if the Language Server is enabled)
 - Validation of functions and types (if the Language Server is enabled)
 - Diagnostic hints, warnings, and errors (if the Language Server is enabled)