fix(revenue): replicate the reference rebate poster canvas layers

The poster modal shell already matched the reference theme, but the canvas
drawing diverged from zibll's poster-share.js rebate branch in four places:

- No 推荐人 tags layer. The reference paints a red #fc4e1f 24px line at
  img_height+160; AKSRT dropped the layer entirely, so the poster lost the
  referrer attribution that identifies whose link it is.
- The logo slot painted text. The reference contains the real logo image
  into (80, height-190, 300, 100); AKSRT drew the site name as a 30px string
  plus a hardcoded 长按识别二维码访问 caption in that slot.
- Bottom copy was hardcoded. The reference reads share_desc; now sourced
  from the new pay_rebate_poster_desc_bottom field with share_desc fallback.
- No banner fallback. The reference walks banner → banner_default →
  banner_spare; a single broken URL left the top half of the poster black.

Also aligns the week label to the reference's 周 prefix (was 星期日) and ports
drawTextOverflow for wrapping/truncation, which retires the local wrapText.

Adds pay_rebate_poster_banner and pay_rebate_poster_desc_bottom to both the
Vue and PHP schemas; rest_me now returns logo, compatible and referrer_name.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

src/Payment/ReferralAttribution.php

@@ -348,12 +348,25 @@ final class ReferralAttribution {
 		$affiliate = \AKSRT\Settings\Settings::get_affiliate_settings();
 		$registration = $this->registration_settings();
 		$reward = $this->reward_settings();
+		$poster = (array) ($affiliate['poster'] ?? ['enabled' => false]);
+		// 参考主题 rebate 海报的 logo 与底部文案取自分享设置，不在推广海报字段里重复配置。
+		if (class_exists('\AKSRT\Settings\Settings')) {
+			$share = \AKSRT\Settings\Settings::get_share_settings();
+			$poster['logo'] = esc_url_raw((string) ($share['poster_logo'] ?? ''));
+			$poster['compatible'] = !empty($share['compatible_s']);
+			if (($poster['bottom'] ?? '') === '') {
+				$poster['bottom'] = sanitize_text_field((string) ($share['share_desc'] ?? ''));
+			}
+		}
+		$user = get_userdata($user_id);
 		return new \WP_REST_Response([
 			'ref' => $link['ref'],
 			'url' => $link['url'],
 			'status' => $link['status'],
 			'site_name' => get_bloginfo('name'),
-			'poster' => (array) ($affiliate['poster'] ?? ['enabled' => false]),
+			// 参考主题 tags：`推荐人: {昵称}`，画在海报主图下方的独立红色标签层。
+			'referrer_name' => $user instanceof WP_User ? $user->display_name : '',
+			'poster' => $poster,
 			'features' => [
 				'registration' => !empty($registration['enabled']),
 				'points_reward' => !empty($reward['enabled']),