tailcfg, util/deephash: add DataPlaneAuditLogID to Node and DomainDataPlaneAuditLogID to MapResponse

We're adding two log IDs to facilitate data-plane audit logging: a node-specific
log ID, and a domain-specific log ID.

Updated util/deephash/deephash_test.go with revised expectations for tailcfg.Node.

Updates https://github.com/tailscale/corp/issues/6991

Signed-off-by: Aaron Klotz <aaron@tailscale.com>

tailcfg/tailcfg_view.go

@@ -173,6 +173,7 @@ func (v NodeView) MachineAuthorized() bool           { return v.ж.MachineAuthor
 func (v NodeView) Capabilities() views.Slice[string] { return views.SliceOf(v.ж.Capabilities) }
 func (v NodeView) ComputedName() string              { return v.ж.ComputedName }
 func (v NodeView) ComputedNameWithHost() string      { return v.ж.ComputedNameWithHost }
+func (v NodeView) DataPlaneAuditLogID() string       { return v.ж.DataPlaneAuditLogID }
 func (v NodeView) Equal(v2 NodeView) bool            { return v.ж.Equal(v2.ж) }
 
 // A compilation failure here means this code must be regenerated, with the command at the top of this file.
@@ -203,6 +204,7 @@ var _NodeViewNeedsRegeneration = Node(struct {
 	ComputedName            string
 	computedHostIfDifferent string
 	ComputedNameWithHost    string
+	DataPlaneAuditLogID     string
 }{})
 
 // View returns a readonly view of Hostinfo.