Move code to a src/ subfolder

Signed-off-by: Severin Kaderli <severin@kaderli.dev>

Dockerfile

@@ -1,3 +1,3 @@
 FROM registry.gitlab.com/severinkaderli/nginx-docker:master
 
-COPY ./ /usr/share/nginx/html
+COPY ./src/ /usr/share/nginx/html

package.json

@@ -4,8 +4,8 @@
         "prettier": "^3.2.4"
     },
     "scripts": {
-        "format": "prettier --write index.html styles.css",
-        "format:check": "prettier  --check index.html styles.css"
+        "format": "prettier --write src/",
+        "format:check": "prettier  --check src/"
     },
     "prettier": "@severinkaderli/prettier-config"
 }