feat(docker): Add flag to enable IPv6 in auto-created networks

internal/pkg/config/config.example.yaml

@@ -58,6 +58,9 @@ container:
   # Could be host, bridge or the name of a custom network.
   # If it's empty, create a network automatically.
   network: ""
+  # Whether to create networks with IPv6 enabled. Requires the Docker daemon to be set up accordingly.
+  # Only takes effect if "network" is set to "".
+  enable_ipv6: false
   # Whether to use privileged mode or not when launching task containers (privileged mode is required for Docker-in-Docker).
   privileged: false
   # And other options to be used when the container is started (eg, --add-host=my.forgejo.url:host-gateway).

internal/pkg/config/config.go

@@ -45,6 +45,7 @@ type Cache struct {
 type Container struct {
 	Network       string   `yaml:"network"`        // Network specifies the network for the container.
 	NetworkMode   string   `yaml:"network_mode"`   // Deprecated: use Network instead. Could be removed after Gitea 1.20
+	EnableIPv6    bool     `yaml:"enable_ipv6"`    // EnableIPv6 indicates whether the network is created with IPv6 enabled.
 	Privileged    bool     `yaml:"privileged"`     // Privileged indicates whether the container runs in privileged mode.
 	Options       string   `yaml:"options"`        // Options specifies additional options for the container.
 	WorkdirParent string   `yaml:"workdir_parent"` // WorkdirParent specifies the parent directory for the container's working directory.