platform: modularize api/gui, add docs-tests-web foundation, and refresh root config

selective-vpn-api/app/routes_cache_helpers_meta.go

@@ -0,0 +1,26 @@
+package app
+
+import (
+	"encoding/json"
+	"os"
+	"strings"
+)
+
+func loadRoutesClearCacheMeta() (routesClearCacheMeta, error) {
+	data, err := os.ReadFile(routesCacheMeta)
+	if err != nil {
+		return routesClearCacheMeta{}, err
+	}
+	var meta routesClearCacheMeta
+	if err := json.Unmarshal(data, &meta); err != nil {
+		return routesClearCacheMeta{}, err
+	}
+	return meta, nil
+}
+
+func ifaceOrDash(iface string) string {
+	if strings.TrimSpace(iface) == "" {
+		return "-"
+	}
+	return iface
+}