[P_UI] Added django settings for p_ui (#5343)

* Added django settings for pui

* Fix: server version is not loaded on initial load

* Moved server version out of server selector icon

* Use polling only for WSL

* Added comment and extracted to constant instead of function

* Default show server selector to false if not in dev mode

* Refactored hostList settings

* Move json serialization into global scope

* Show server selector in netlify builds

* Use demo server for netlify

* Renamed netilfy mode to dev or demo mode

* Translate for netlify

* Dont use translation in main as the are not working there

src/frontend/vite.config.ts

@@ -1,6 +1,9 @@
 import react from '@vitejs/plugin-react';
+import { platform } from 'node:os';
 import { defineConfig, splitVendorChunkPlugin } from 'vite';
 
+const IS_IN_WSL = platform().includes('WSL');
+
 // https://vitejs.dev/config/
 export default defineConfig({
   plugins: [
@@ -16,8 +19,17 @@ export default defineConfig({
     outDir: '../../InvenTree/web/static/web'
   },
   server: {
+    proxy: {
+      '/api': {
+        target: 'http://localhost:8000',
+        changeOrigin: true,
+        secure: true
+      }
+    },
     watch: {
-      usePolling: true
+      // use polling only for WSL as the file system doesn't trigger notifications for Linux apps
+      // ref: https://github.com/vitejs/vite/issues/1153#issuecomment-785467271
+      usePolling: IS_IN_WSL
     }
   }
 });