feat(download): switch download buttons to direct source links

The token relay still stood between the button and the file: every click
issued a short-lived token URL, so downloads never reached the real
source address directly.

- Render direct anchors (target=_blank) to the raw source URL in the
  download box and the paid card, with inline extract-code buttons
- Retire the relay: delete Content\Download plus its init wiring, header
  query-var branch and SEO noindex branch, and drop the dead
  download-request flow from cms-download.js (cashier, scan-pay and
  error views stay)
- Keep the dl_token table and the download logs page as read-only
  history; unscheduling of the orphaned cleanup cron is preserved

assets/js/cms-download.js

@@ -2,9 +2,9 @@
  * AKSRT CMS Download
  *
  * 功能：
- *   - 监听 [data-action="aksrt-download"] 按钮点击
- *   - 调 POST /aksrt/v1/download/request
- *   - 成功后直接打开生成的下载链接；失败/购买等场景仍走弹窗
+ *   - 监听购买入口（data-aksrt-pay-content / data-action="aksrt-need-purchase"）
+ *   - 内容购买收银台、扫码支付与错误提示弹窗
+ *   - 下载已改为直连：按钮为源地址锚点，不再经过本站中转请求
  *
  * 弹窗视觉走主题 design token（见 assets/css/frontend/cms-download.css），
  * 付费收银台沿用参考实现的 colorful header 结构。
@@ -140,7 +140,6 @@
 	// ===== 统一视图壳（下载 / 错误 / 扫码共用主题化外观） =====
 	// 头部与按钮统一继承运行时主题色（--focus-color），状态用图标 + 标题区分。
 	const DL_VIEWS = {
-		success:  { icon: 'fa-cloud-download-alt', title: '下载已就绪' },
 		login:    { icon: 'fa-user-lock',          title: '请先登录' },
 		purchase: { icon: 'fa-shopping-cart',      title: '请先购买' },
 		vip:      { icon: 'fa-gem',                title: '会员专属' },
@@ -251,34 +250,8 @@
 		}
 	}
 
-	// ===== 成功：直接打开生成的下载链接，不再弹窗 =====
-	function startDownload(payload, returnFocusEl) {
-		const url = payload && payload.dl_url ? String(payload.dl_url) : '';
-		if (!url) {
-			renderError('下载链接生成失败，请稍后重试', {}, returnFocusEl);
-			return;
-		}
-		// 与旧版弹窗内「立即下载」一致：新标签页打开本站中转链接。
-		const link = document.createElement('a');
-		link.href = url;
-		link.target = '_blank';
-		link.rel = 'noopener noreferrer';
-		document.body.appendChild(link);
-		link.click();
-		link.remove();
-	}
 
-	// ===== 主流程 =====
-		function captchaScope(sourceEl) {
-			const box = sourceEl ? sourceEl.closest('[data-aksrt-download-box]') : null;
-			return box ? (box.querySelector('[data-aksrt-download-captcha]') || box) : sourceEl;
-		}
 
-		function isCaptchaActive(sourceEl) {
-		const card = sourceEl ? sourceEl.closest('[data-aksrt-download-box]') : null;
-		if (!card) return false;
-		return card.getAttribute('data-captcha') === '1';
-	}
 
 	function cashierHeader() {
 		return '<div class="modal-colorful-header colorful-bg jb-blue">' +
@@ -299,70 +272,8 @@
 		);
 	}
 
-		function ensureCaptchaThen(sourceEl, callback) {
-			if (!isCaptchaActive(sourceEl)) { callback({}); return; }
-			const captcha = window.AKSRTCaptcha;
-			if (!captcha) {
-				if (window.console && console.warn) console.warn('[AKSRT] download captcha not ready');
-				alert('验证码组件加载中，请稍候再试');
-				return;
-			}
-			captcha.run('download', captchaScope(sourceEl)).then(function (payload) {
-				if (payload !== null) callback(payload);
-			});
-		}
 
-		function performDownloadRequest(button, captchaPayload) {
-		const card = button.closest('[data-aksrt-download-box]');
-		if (!card) return;
-		const postId = parseInt(card.getAttribute('data-post-id'), 10);
-		const sourceIndex = parseInt(button.getAttribute('data-source-index'), 10);
-		if (!postId || isNaN(sourceIndex)) return;
 
-		button.disabled = true;
-		const original = button.innerHTML;
-		button.innerHTML = '<i class="fa fas fa-spinner fa-spin" aria-hidden="true"></i> 处理中…';
-
-			const restNonce = window.aksrtData.restNonce || '';
-
-			fetch(REST_BASE + '/download/request', {
-			method: 'POST',
-			credentials: 'same-origin',
-			headers: {
-				'Content-Type': 'application/json',
-				'X-WP-Nonce': restNonce,
-			},
-			body: JSON.stringify({
-				post_id: postId,
-				source_index: sourceIndex,
-				captcha: captchaPayload,
-			}),
-		})
-			.then(function (resp) { return resp.json().then(function (j) { return { ok: resp.ok, json: j }; }); })
-			.then(function (r) {
-				button.disabled = false;
-				button.innerHTML = original;
-					if (!r.ok || (r.json && r.json.code)) {
-						renderError(r.json.message || '请稍后重试', r.json.data || {}, button, r.json.code);
-						return;
-					}
-				startDownload(r.json, button);
-			})
-				.catch(function () {
-					button.disabled = false;
-					button.innerHTML = original;
-					renderError('网络错误，请稍后重试', {}, button);
-				})
-				.finally(function () {
-					if (window.AKSRTCaptcha) window.AKSRTCaptcha.reset('download', captchaScope(button));
-				});
-		}
-
-		function requestDownload(button) {
-			ensureCaptchaThen(button, function (captchaPayload) {
-				performDownloadRequest(button, captchaPayload);
-			});
-	}
 
 	function pollOrderPaid(orderNumber, returnFocusEl) {
 		if (!orderNumber) return;
@@ -387,12 +298,6 @@
 		}, 3000);
 	}
 
-	// ===== 积分不足按钮（前置拦截，不发请求） =====
-	function showLowCreditModal(button) {
-		const balance = parseInt(button.getAttribute('data-balance'), 10) || 0;
-		const cost = parseInt(button.getAttribute('data-cost'), 10) || 0;
-		renderError('', { balance: balance, cost: cost }, button, 'aksrt_points_insufficient');
-	}
 
 	// ===== 收银台（内容购买） =====
 	function restHeaders(idempotencyKey) {
@@ -807,13 +712,6 @@
 
 	// ===== 事件绑定 =====
 	document.addEventListener('click', function (e) {
-		const lowBtn = e.target.closest('[data-action="aksrt-need-credits"]');
-		if (lowBtn) {
-			e.preventDefault();
-			showLowCreditModal(lowBtn);
-			return;
-		}
-
 		const buyBtn = e.target.closest('[data-action="aksrt-need-purchase"], [data-aksrt-pay-content]');
 		if (buyBtn) {
 			e.preventDefault();
@@ -828,12 +726,6 @@
 			if (postId) openCashier(postId, buyBtn, priceType);
 			return;
 		}
-
-		const btn = e.target.closest('[data-action="aksrt-download"]');
-		if (!btn) return;
-		if (btn.disabled || btn.getAttribute('aria-disabled') === 'true') return;
-		e.preventDefault();
-		requestDownload(btn);
 	});
 
 	// Public cashier bridge (content pay).