feat(identity): tip QR upload, metrics engine, comment moderate caps

Close identity 1:1 gaps after p1: user-center weixin/alipay tip QR
upload+save, AKSRT_User_Metrics counters for medal get_type and level
XP bridges, forum/revenue/signin hooks, comment moderate via user_caps,
and clearer free-task deep links/status CTAs.

assets/css/routes/user-center/settings.css

@@ -325,3 +325,37 @@
   color: var(--color-ink-4);
   background: transparent;
 }
+
+
+/* Tip QR upload on profile */
+.aksrt-reward-upload-grid {
+  display: grid;
+  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
+  gap: 16px;
+  margin-top: 12px;
+}
+.aksrt-reward-upload__preview {
+  min-height: 140px;
+  border: 1px dashed rgba(127,127,127,.35);
+  border-radius: 10px;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  overflow: hidden;
+  margin: 8px 0;
+  background: rgba(127,127,127,.04);
+}
+.aksrt-reward-upload__preview img {
+  max-width: 100%;
+  max-height: 180px;
+  object-fit: contain;
+  display: block;
+}
+.aksrt-reward-upload__file {
+  display: none;
+}
+.aksrt-reward-upload .btn-sm,
+.aksrt-reward-upload .btn-primary {
+  margin-right: 8px;
+  margin-top: 4px;
+}