stdlib/os/container: added ability to mount sockets (dagger.#Stream)

Signed-off-by: Sam Alba <samalba@users.noreply.github.com>

stdlib/os/container.cue

@@ -54,6 +54,9 @@ import (
 	// Safely mount secrets (in cleartext) as non-persistent files
 	secret: [string]: dagger.#Secret
 
+	// Mount unix socket or windows npipes to the corresponding path
+	socket: [string]: dagger.#Stream
+
 	// Write file in the container
 	files: [string]: {
 		content: string
@@ -120,6 +123,9 @@ import (
 					for dest, _ in tmpfs {
 						"\(dest)": "tmpfs"
 					}
+					for dest, s in socket {
+						"\(dest)": stream: s
+					}
 				}
 			}
 		},