Add NetworkSpec struct with optional Subnet field to ScenarioSpec.Networks.
When Subnet is set, the Docker network is created with that specific CIDR
instead of Docker's auto-assigned RFC1918 range.
Fix all exit node integration tests to use curl + traceroute. Tailscale
exit nodes strip locally-connected subnets from their forwarding filter
(shrinkDefaultRoute + localInterfaceRoutes), so exit nodes cannot
forward to IPs on their Docker network via the default route alone.
This is by design: exit nodes provide internet access, not LAN access.
To also get LAN access, the subnet must be explicitly advertised as a
route — matching real-world Tailscale deployment requirements.
- TestSubnetRouterMultiNetworkExitNode: advertise usernet1 subnet
alongside exit route, upgraded from ping to curl + traceroute
- TestGrantViaExitNodeSteering: usernet1 subnet in via grants and
auto-approvers alongside autogroup:internet
- TestGrantViaMixedSteering: externet subnet in auto-approvers and
route advertisement for exit traffic
Updates #2180
Add NodeAttrsTaildriveShare and NodeAttrsTaildriveAccess to the node capability map, enabling Taildrive file sharing when granted via policy. Add integration test verifying the full cap/drive grant lifecycle.
Updates #2180
Add ConnectToNetwork to the TailscaleClient interface for multi-network test scenarios and implement peer relay ping support. Use these to test that cap/relay grants correctly enable peer-to-peer relay connections between tagged nodes.
Updates #2180
