feat(pay): VIP package purchase service and user-center open flow

Add AKSRT_Vip_Service (GET/POST /pay/vip), activate aksrt_vip_level/expires on
order paid, package UI in credits panel, and deep-link VIP CTA to credits tab.

assets/js/credits.js

@@ -317,13 +317,98 @@
 		});
 	}
 
+
+	// ===== VIP 开通 =====
+	function initVipShop() {
+		var root = document.querySelector('[data-aksrt-vip-shop]');
+		if (!root) return;
+		var tip = root.querySelector('[data-aksrt-vip-tip]');
+		var busy = false;
+
+		function setTip(text, isError) {
+			if (!tip) return;
+			tip.textContent = text || '';
+			tip.classList.toggle('is-error', !!isError);
+		}
+
+		function selectedMethod() {
+			var fixed = root.querySelector('[data-aksrt-vip-method-fixed]');
+			if (fixed && fixed.value) return fixed.value;
+			var checked = root.querySelector('input[name="aksrt_vip_pay_method"]:checked');
+			if (checked) return checked.value;
+			var first = root.querySelector('input[name="aksrt_vip_pay_method"]');
+			return first ? first.value : 'balance';
+		}
+
+		function pollOrder(orderNumber) {
+			if (!orderNumber) return;
+			var tries = 0;
+			var maxTries = 40;
+			var timer = setInterval(function () {
+				tries += 1;
+				api('/pay/content/order/' + encodeURIComponent(orderNumber)).then(function (r) {
+					if (r.ok && r.json && r.json.paid) {
+						clearInterval(timer);
+						setTip('支付成功，正在刷新…');
+						window.location.reload();
+					}
+				}).catch(function () { /* ignore */ });
+				if (tries >= maxTries) clearInterval(timer);
+			}, 3000);
+		}
+
+		root.addEventListener('click', function (e) {
+			var btn = e.target.closest('[data-aksrt-vip-buy]');
+			if (!btn || busy) return;
+			e.preventDefault();
+			var packageId = parseInt(btn.getAttribute('data-package-id') || '0', 10);
+			if (!packageId) return;
+			busy = true;
+			btn.classList.add('is-loading');
+			setTip('正在创建订单…');
+
+			api('/pay/vip', {
+				method: 'POST',
+				body: JSON.stringify({
+					package_id: packageId,
+					payment_method: selectedMethod()
+				})
+			}).then(function (r) {
+				busy = false;
+				btn.classList.remove('is-loading');
+				if (!r.ok || (r.json && r.json.code && !r.json.success)) {
+					var msg = (r.json && r.json.message) || '开通失败';
+					setTip(msg, true);
+					return;
+				}
+				var data = (r.json && r.json.data) ? r.json.data : r.json;
+				if (data && data.redirect && (data.payment_url || data.qr_content)) {
+					if (data.payment_url) {
+						window.open(data.payment_url, '_blank');
+					}
+					setTip(data.message || '请完成支付，支付成功后将自动刷新。');
+					if (data.order_number) pollOrder(data.order_number);
+					return;
+				}
+				setTip((data && data.message) || '开通成功，正在刷新…');
+				window.location.reload();
+			}).catch(function () {
+				busy = false;
+				btn.classList.remove('is-loading');
+				setTip('网络错误，请重试', true);
+			});
+		});
+	}
+
 	if (document.readyState === 'loading') {
 		document.addEventListener('DOMContentLoaded', function () {
 			initSignin();
 			initInvite();
+			initVipShop();
 		});
 	} else {
 		initSignin();
 		initInvite();
+		initVipShop();
 	}
 })();