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

selective-vpn-api/app/helpers_values.go

@@ -0,0 +1,30 @@
+package app
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+func parsePort(raw string) int {
+	p := strings.TrimSpace(raw)
+	if p == "" {
+		return 0
+	}
+	n, err := strconv.Atoi(p)
+	if err != nil || n <= 0 || n > 65535 {
+		return 0
+	}
+	return n
+}
+
+func asString(v any) string {
+	switch vv := v.(type) {
+	case string:
+		return strings.TrimSpace(vv)
+	case nil:
+		return ""
+	default:
+		return strings.TrimSpace(fmt.Sprint(vv))
+	}
+}