upgrade to yaml.v3 (#1148)

* upgrade to yaml.v3

The main nice fix here is that maps unmarshal into `map[string]any`
instead of `map[any]any`, so it cleans things up a bit.

* add config.AsBool

Since yaml.v3 doesn't automatically convert yes to bool now, for
backwards compat

* use type aliases for m

* more cleanup

* more cleanup

* more cleanup

* go mod cleanup

overlay/route.go

@@ -72,7 +72,7 @@ func parseRoutes(c *config.C, networks []netip.Prefix) ([]Route, error) {
 		return []Route{}, nil
 	}
 
-	rawRoutes, ok := r.([]interface{})
+	rawRoutes, ok := r.([]any)
 	if !ok {
 		return nil, fmt.Errorf("tun.routes is not an array")
 	}
@@ -83,7 +83,7 @@ func parseRoutes(c *config.C, networks []netip.Prefix) ([]Route, error) {
 
 	routes := make([]Route, len(rawRoutes))
 	for i, r := range rawRoutes {
-		m, ok := r.(map[interface{}]interface{})
+		m, ok := r.(map[string]any)
 		if !ok {
 			return nil, fmt.Errorf("entry %v in tun.routes is invalid", i+1)
 		}
@@ -151,7 +151,7 @@ func parseUnsafeRoutes(c *config.C, networks []netip.Prefix) ([]Route, error) {
 		return []Route{}, nil
 	}
 
-	rawRoutes, ok := r.([]interface{})
+	rawRoutes, ok := r.([]any)
 	if !ok {
 		return nil, fmt.Errorf("tun.unsafe_routes is not an array")
 	}
@@ -162,7 +162,7 @@ func parseUnsafeRoutes(c *config.C, networks []netip.Prefix) ([]Route, error) {
 
 	routes := make([]Route, len(rawRoutes))
 	for i, r := range rawRoutes {
-		m, ok := r.(map[interface{}]interface{})
+		m, ok := r.(map[string]any)
 		if !ok {
 			return nil, fmt.Errorf("entry %v in tun.unsafe_routes is invalid", i+1)
 		}