docs: split Compose docs into reference and concepts

website/docs/8-compose-file-reference/1-support-matrix.md

@@ -83,7 +83,7 @@ services:
       - 8080:80/tcp@host
 ```
 
-See [Publishing services](../1-ingress/2-publishing-services.md) for more details.
+See [Publishing services](../3-concepts/1-ingress/2-publishing-services.md) for more details.
 
 ### `x-caddy`
 
@@ -99,7 +99,7 @@ services:
       }
 ```
 
-See [Publishing services](../1-ingress/2-publishing-services.md) for more details.
+See [Publishing services](../3-concepts/1-ingress/2-publishing-services.md) for more details.
 
 ### `x-machines`
 

website/docs/8-compose-file-reference/_category_.yaml

@@ -1,4 +1,4 @@
-label: Compose features
+label: Compose file reference
 collapsed: true # keep the category closed by default
 link:
   type: generated-index