Add Matrix homeserver with MatrixRTC calling support

- Synapse + PostgreSQL + coturn + LiveKit + lk-jwt-service
- Caddy entries for mtx.alogins.net, lk.alogins.net, lkjwt.alogins.net
- well-known endpoints for Matrix client/server discovery and RTC transport
- Users: admin, elizaveta, aleksandra

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

matrix/.env

@@ -0,0 +1,7 @@
+SYNAPSE_DATA=./data/synapse
+POSTGRES_DATA=./data/postgres
+POSTGRES_USER=synapse
+POSTGRES_PASSWORD=OimW4JUSXhZBCtLHE1kFnZ7cWVbESsxynapnJ+PSw/4=
+POSTGRES_DB=synapse
+LIVEKIT_KEY=devkey
+LIVEKIT_SECRET=ef3ef4b903ca8469b09b2dd7ab6af529c4d2f3c95668f53832fc351cf67777a9