call: consume self-built Element Call fork + activate Lotus features

Switch to @lotusguild/element-call-embedded@0.20.1-lotus.1 (our self-built
fork) and turn on the source-level features it adds:

- #1 denoise CUTOVER: in-source ML denoise (lotusDenoiseSource=1) replaces
  the build-time getUserMedia shim — removed the shim injection from
  vite.config.js (denoise/ assets still shipped; the processor loads them).
  Survives reconnects (fixes A7).
- #2 call-state: CallEmbed consumes io.lotus.call_state; useCallSpeakers /
  useRemoteAllMuted prefer it over scraping EC's DOM (DOM fallback kept;
  empty payloads ignored).
- #4 focus: CallControl.focusCameraParticipant sends io.lotus.focus_participant
  (works during screenshare), replacing the DOM tile-click hack.
- #5 theming: lotusTransparent=1 (native transparent background).
- #6 decorations: LotusDecorationPusher sends each member's decoration URL
  via io.lotus.decorations -> rendered on in-call tiles.

#3 soundboard / #7 quality ship dormant (EC-ready; no host UI sends them yet).

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

package-lock.json

@@ -77,7 +77,7 @@
         "ua-parser-js": "2.0.10"
       },
       "devDependencies": {
-        "@element-hq/element-call-embedded": "0.20.1",
+        "@lotusguild/element-call-embedded": "0.20.1-lotus.1",
         "@rollup/plugin-inject": "5.0.5",
         "@rollup/plugin-wasm": "6.2.2",
         "@types/chroma-js": "3.1.2",
@@ -1788,12 +1788,6 @@
         "node": ">=v18"
       }
     },
-    "node_modules/@element-hq/element-call-embedded": {
-      "version": "0.20.1",
-      "resolved": "https://registry.npmjs.org/@element-hq/element-call-embedded/-/element-call-embedded-0.20.1.tgz",
-      "integrity": "sha512-ODg2r7UmR8UjRpapLKbn6v1PS8fu/r58zdbvXMYaAlUEAC2f6L/9Moc9S4noG1+ARgWxY+m2vLmNDK9G9uFZYQ==",
-      "dev": true
-    },
     "node_modules/@emnapi/core": {
       "version": "1.10.0",
       "resolved": "https://registry.npmjs.org/@emnapi/core/-/core-1.10.0.tgz",
@@ -2693,6 +2687,12 @@
       "resolved": "https://registry.npmjs.org/@juggle/resize-observer/-/resize-observer-3.4.0.tgz",
       "integrity": "sha512-dfLbk+PwWvFzSxwk3n5ySL0hfBog779o8h68wK/7/APo/7cgyWp5jcXockbxdk5kFRkbeXWm4Fbi9FrdN381sA=="
     },
+    "node_modules/@lotusguild/element-call-embedded": {
+      "version": "0.20.1-lotus.1",
+      "resolved": "https://code.lotusguild.org/api/packages/LotusGuild/npm/%40lotusguild%2Felement-call-embedded/-/0.20.1-lotus.1/element-call-embedded-0.20.1-lotus.1.tgz",
+      "integrity": "sha512-hy1KEnFw4MuwvlactUFPPvvtPZh1y56JMK/ehnficUmJNwdJsOhSwThaYp35RZ/ar6RCuiW86yQqlQBOSpZJVQ==",
+      "dev": true
+    },
     "node_modules/@matrix-org/matrix-sdk-crypto-wasm": {
       "version": "18.3.0",
       "resolved": "https://registry.npmjs.org/@matrix-org/matrix-sdk-crypto-wasm/-/matrix-sdk-crypto-wasm-18.3.0.tgz",