feat(assets): forum free-task depth, withdraw notices, share poster

Route forum essence/adopt/hot/score rewards through free-points day cap,
notify users on withdraw complete/reject, surface 海报分享 on single
share grid, and extend admin free-task keys for the remaining matrix.

inc/helpers/aksrt-single-render.php

@@ -236,6 +236,7 @@ if (!function_exists('aksrt_single_render_actions')) :
 					<button type="button" class="share-item" data-platform="twitter"><i class="fab fa-x-twitter"></i><span>X</span></button>
 					<button type="button" class="share-item" data-platform="wechat"><i class="fab fa-weixin"></i><span>微信</span></button>
 					<button type="button" class="share-item" data-platform="copy"><i class="fas fa-link"></i><span><?php esc_html_e('复制链接', 'aksrt'); ?></span></button>
+					<button type="button" class="share-item" data-platform="poster"><i class="fas fa-image"></i><span><?php esc_html_e('海报分享', 'aksrt'); ?></span></button>
 				</div>
 				<div id="share-qrcode-box" aria-hidden="true"><img id="share-qrcode-image" src="" alt="QR Code"></div>
 			</div>