feat(web): complete groups/contacts/favorites/settings/calls/system domains + extensive review-round fixes

Rounds out the full rewrite with the remaining feature domains: group
management (admin panel, mute, files, announcements, QR-based invite/join),
contacts (friend profile, add-friend, blocklist, new-friends), favorites
(real media rendering across text/image/video/voice/file/link), settings
(profile/security/privacy/general/about), calls (Agora-backed audio/video
signaling + call history), and system messages/file assistant.

Also folds in a large batch of live-verified fixes surfaced by repeated
fresh code-review passes and hands-on E2E testing against the real
backend, including: WS reconnect not resubscribing any topic after a
disconnect, missing x-im-client-mid on every send path (protocol
compliance for retry dedup), group mute/member-settings/self-profile
endpoint corrections, relationship-state type fixes across search/QR/
friend-profile, tenant-switch logout gap, password-policy now read from
the real per-tenant config instead of guessed, NavRail highlight/
aria-current desync, several call-state-machine races, and responsive
layout fixes across all four breakpoints (mobile/tablet/laptop/desktop)
including a full mobile rebuild of favorites, call UI, and the settings
home/sub-list split.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

web/src/index.css

@@ -103,7 +103,7 @@
 
   /* Shadows */
   --shadow-card: 0 8px 32px rgba(35, 74, 125, 0.10);
-  --shadow-modal: 0 20px 60px rgba(0, 0, 0, 0.2);
+  --shadow-modal: 0 20px 60px rgba(0, 0, 0, 0.18);
   --shadow-menu: 0 12px 36px rgba(0, 0, 0, 0.16);
   --shadow-bubble: 0 1px 2px rgba(0, 0, 0, 0.06);
   /* screens/01-account.dc.html's 50px auth CTAs (登录/注册/提交...). */
@@ -114,6 +114,19 @@
   --shadow-focus-ring: 0 0 0 3px rgba(22, 119, 255, 0.1);
 }
 
+/* MessageRow's jump-to-message flash (ConversationView, 查找聊天记录 result click) -- a brief
+   background pulse marking the message the user asked to find, fading back to transparent so it
+   doesn't look like a permanent selection state. */
+@keyframes jump-highlight {
+  0%,
+  30% {
+    background-color: var(--color-accent-soft-bg);
+  }
+  100% {
+    background-color: transparent;
+  }
+}
+
 body {
   margin: 0;
   background: var(--color-surface-page);