docs: added zitadel-vanilla-js link and reference (#10807)

Added a link to the new vanilla-js SPA example on the sidebar, and the
card + image on the resources here:
- https://zitadel.com/docs/sdk-examples/introduction 

New sample app:
- https://github.com/zitadel/zitadel-vanilla-js

docs/frameworks.json

@@ -164,5 +164,11 @@
 		"imgSrcDark": "/docs/img/tech/pylon.svg",
 		"docsLink": "https://github.com/getcronit/pylon",
 		"external": true
+	},
+		{
+		"title": "Vanilla-JS",
+		"imgSrcDark": "/docs/img/tech/javascript.svg",
+		"docsLink": "https://github.com/zitadel/zitadel-vanilla-js",
+		"external": true
 	}
 ]

docs/sidebars.js

@@ -125,6 +125,11 @@ module.exports = {
           label: "Pylon",
           href: "https://github.com/getcronit/pylon",
         },
+        {
+          type: "link",
+          label: "Vanilla-JS",
+          href: "https://github.com/zitadel/zitadel-vanilla-js",
+        },
       ],
     },
     {

docs/static/img/tech/javascript.svg

@@ -0,0 +1,2 @@
+<?xml version="1.0" encoding="utf-8"?><!-- Uploaded to: SVG Repo, www.svgrepo.com, Generator: SVG Repo Mixer Tools -->
+<svg width="800px" height="800px" viewBox="0 0 256 256" xmlns="http://www.w3.org/2000/svg" preserveAspectRatio="xMinYMin meet"><path d="M0 0h256v256H0V0z" fill="#F7DF1E"/><path d="M67.312 213.932l19.59-11.856c3.78 6.701 7.218 12.371 15.465 12.371 7.905 0 12.89-3.092 12.89-15.12v-81.798h24.057v82.138c0 24.917-14.606 36.259-35.916 36.259-19.245 0-30.416-9.967-36.087-21.996M152.381 211.354l19.588-11.341c5.157 8.421 11.859 14.607 23.715 14.607 9.969 0 16.325-4.984 16.325-11.858 0-8.248-6.53-11.17-17.528-15.98l-6.013-2.58c-17.357-7.387-28.87-16.667-28.87-36.257 0-18.044 13.747-31.792 35.228-31.792 15.294 0 26.292 5.328 34.196 19.247L210.29 147.43c-4.125-7.389-8.591-10.31-15.465-10.31-7.046 0-11.514 4.468-11.514 10.31 0 7.217 4.468 10.14 14.778 14.608l6.014 2.577c20.45 8.765 31.963 17.7 31.963 37.804 0 21.654-17.012 33.51-39.867 33.51-22.339 0-36.774-10.654-43.819-24.574"/></svg>