Merge upstream v4.12.3 (Element Call 0.20.1) into lotus

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

package.json

@@ -1,6 +1,6 @@
 {
   "name": "lotus-chat",
-  "version": "4.12.2-lotus",
+  "version": "4.12.3-lotus",
   "description": "Lotus Chat — Matrix client for Lotus Guild",
   "main": "index.js",
   "type": "module",
@@ -103,7 +103,7 @@
     "ua-parser-js": "2.0.10"
   },
   "devDependencies": {
-    "@element-hq/element-call-embedded": "0.19.4",
+    "@element-hq/element-call-embedded": "0.20.1",
     "@rollup/plugin-inject": "5.0.5",
     "@rollup/plugin-wasm": "6.2.2",
     "@sentry/vite-plugin": "5.3.0",