Upgrade to fontawesome 6

* Adapt fontawesome usage when needed
* Fix uv guide not importing css
* Remove utf8 usage for fontawesome

package-lock.json

@@ -9,6 +9,7 @@
             "version": "3",
             "license": "GPL-3.0-only",
             "dependencies": {
+                "@fortawesome/fontawesome-free": "^6.6.0",
                 "alpinejs": "^3.14.1",
                 "easymde": "^2.18.0",
                 "glob": "^11.0.0",
@@ -1825,6 +1826,14 @@
                 "node": ">=10.0.0"
             }
         },
+        "node_modules/@fortawesome/fontawesome-free": {
+            "version": "6.6.0",
+            "resolved": "https://registry.npmjs.org/@fortawesome/fontawesome-free/-/fontawesome-free-6.6.0.tgz",
+            "integrity": "sha512-60G28ke/sXdtS9KZCpZSHHkCbdsOGEhIUGlwq6yhY74UpTiToIh8np7A8yphhM4BWsvNFtIvLpi4co+h9Mr9Ow==",
+            "engines": {
+                "node": ">=6"
+            }
+        },
         "node_modules/@isaacs/cliui": {
             "version": "8.0.2",
             "resolved": "https://registry.npmjs.org/@isaacs/cliui/-/cliui-8.0.2.tgz",