types: move DebugRoutes from routes to types

Unblocks deletion of the routes package.

Updates #3203

hscontrol/types/debug_routes.go

@@ -0,0 +1,22 @@
+package types
+
+import "net/netip"
+
+// DebugRoutes is the JSON-shaped snapshot of the headscale primary
+// route ledger exposed by the /debug/routes endpoint and consumed by
+// the integration test harness. It used to live in hscontrol/routes,
+// but the algorithm now runs inside hscontrol/state and that package
+// must not be imported from integration code.
+type DebugRoutes struct {
+	// AvailableRoutes maps node IDs to their advertised routes
+	// (intersection of announced and approved). Only nodes currently
+	// connected to headscale are listed.
+	AvailableRoutes map[NodeID][]netip.Prefix `json:"available_routes"`
+
+	// PrimaryRoutes maps route prefixes to the node currently elected
+	// primary for that prefix.
+	PrimaryRoutes map[string]NodeID `json:"primary_routes"`
+
+	// UnhealthyNodes lists nodes that have failed health probes.
+	UnhealthyNodes []NodeID `json:"unhealthy_nodes,omitempty"`
+}