fix(element-call): limit codec dropdown to codecs the SFU actually supports

Live-verified via matrix-rtc-sfu logs: VP9 gets silently rejected and
falls back to VP8 (SFU's enabledPublishCodecs is [VP8, H264, H265], no
VP9/AV1). Dropdown now only offers those three; also fixed
screenShareCodec's default which was "vp9" (fork commit ac99cc65 in
threadnet-call).

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

apps/production/element-server-suite.yaml

@@ -81,7 +81,7 @@ spec:
       image:
         registry: rohana.axion1337.de
         repository: sorb/threadnet-web
-        tag: v0.2.5-elementcall-de-i18n
+        tag: v0.2.6-elementcall-realcodecs
       ingress:
         host: axion1337.chat