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/lib/config.ts

@@ -2,7 +2,7 @@
 // must match the backend (server/*.go) -- they are not stylistic choices, so the numbers/strings
 // themselves carry over unchanged even though this is a from-scratch rewrite.
 
-/** Version-independent product name (Firebase app name, youth-mode copy, etc.). */
+/** Version-independent product name (Firebase app name, in-app copy, etc.). */
 export const BASE_APP_NAME = 'MeetingIM';
 
 /** Name used in the Tinode client's User-Agent string. */
@@ -62,7 +62,8 @@ export const VIDEO_THUMBNAIL_WIDTH = 48;
 
 export const MAX_ONLINE_IN_TOPIC = 4;
 export const MAX_TITLE_LENGTH = 60;
-export const MAX_TOPIC_DESCRIPTION_LENGTH = 360;
+/** docs/IM-前后端对接文档.md:1445 -- "description 可省略或传空字符串，最长 200 字符". */
+export const MAX_TOPIC_DESCRIPTION_LENGTH = 200;
 export const MAX_PEER_TITLE_LENGTH = 24;
 
 export const MESSAGE_PREVIEW_LENGTH = 80;
@@ -82,4 +83,4 @@ export const QRCODE_SIZE = 128;
 export const WAKE_UP_TIMEOUT = 80_000;
 export const WAKE_UP_TICK = 1_000;
 
-export const TOAST_DURATION = 3_000;
+export const TOAST_DURATION = 2_500;