feat: add node help system and registry for extensible node types

- Implemented a help system for different node types (config, render, variable, function) with detailed usage instructions.
- Created a node registry to manage node types, including registration, retrieval, and validation of connections between nodes.
- Defined central node and edge types for the application to streamline state management.
- Added Nunjucks autocomplete functionality to enhance user experience in template editing.
- Developed a syntax highlighting parser for PlantUML and Nunjucks within the CodeMirror editor.
- Registered built-in node types at application startup, including their default configurations and help entries.
- Introduced a theme context provider to manage light/dark mode preferences across the application.
- Created utility functions for class name management using clsx and tailwind-merge.
- Set up Tailwind CSS for styling with custom themes and responsive design.
- Configured Vite for development with proxy settings for backend API calls and Kroki diagram service.

frontend/tsconfig.json

@@ -0,0 +1,34 @@
+{
+    "compilerOptions": {
+        "target": "ESNext",
+        "useDefineForClassFields": true,
+        "lib": [
+            "DOM",
+            "DOM.Iterable",
+            "ESNext"
+        ],
+        "skipLibCheck": true,
+        "esModuleInterop": true,
+        "allowSyntheticDefaultImports": true,
+        "strict": true,
+        "forceConsistentCasingInFileNames": true,
+        "module": "ESNext",
+        "moduleResolution": "Node",
+        "resolveJsonModule": true,
+        "isolatedModules": true,
+        "noEmit": true,
+        "jsx": "react-jsx",
+        "baseUrl": ".",
+        "paths": {
+            "@/*": [
+                "src/*"
+            ],
+            "@": [
+                "src"
+            ]
+        }
+    },
+    "include": [
+        "src"
+    ]
+}