add simple wireguard support

cmd/dkl-local-server/render-context.go

@@ -266,6 +266,20 @@ func (ctx *renderContext) TemplateFuncs() map[string]any {
 
 			return
 		},
+		"wg_key": func(name string) (key string, err error) {
+			return wgKey(name + "/hosts/" + ctx.Host.Name)
+		},
+		"wg_psk": func(name, peerName string) (key string, err error) {
+			a := ctx.Host.Name
+			b := peerName
+			if a > b {
+				a, b = b, a
+			}
+			return wgKey(name + "/psks/" + a + " " + b)
+		},
+		"wg_pubkey": func(name, host string) (key string, err error) {
+			return wgKey(name + "/hosts/" + host)
+		},
 	} {
 		funcs[name] = method
 	}