Add Swagger API documentation and proxy routing.

Added Swagger as a new service in the docker-compose file for generating the API documentation. The new API documentation is provided via an OpenAPI file located at `public/swagger.json`. Changes in routing were done to handle /api-docs requests and redirect them to the running Swagger UI instance. This will make API easier to understand and debug.

docker/dev/angie/config/default.conf

@@ -8,8 +8,16 @@ server {
     root /var/www/html/public;
 
     location / {
-        # try to serve file directly, fallback to index.php
-        try_files $uri /index.php$is_args$args;
+        location /api-docs {
+            proxy_pass http://swagger:8080;
+            proxy_set_header Host $host;
+            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+            proxy_set_header X-Real-IP $remote_addr;
+        }
+        location / {
+            # try to serve file directly, fallback to index.php
+            try_files $uri /index.php$is_args$args;
+        }
     }
 
     location ~ ^/index\.php(/|$) {