chore(infra): update dev compose, add playwright e2e suite & assets

deploy/compose/compose.dev.yaml

@@ -33,6 +33,7 @@ services:
     environment:
       DEV_MODE: ${DEV_MODE:-false}
       SEED_CURRICULUM: ${SEED_CURRICULUM:-false}
+      CAPTCHA_EXPOSE_ANSWER: ${CAPTCHA_EXPOSE_ANSWER:-false}
     deploy:
       resources:
         limits:
@@ -66,6 +67,8 @@ services:
       # Allow slow, large uploads (admin video ≤ 200MB); default is 60s.
       - --entrypoints.web.transport.respondingTimeouts.readTimeout=3600
       - --entrypoints.websecure.transport.respondingTimeouts.readTimeout=3600
+      # Disable HTTP/2 so WebSocket upgrades work from Chromium (RFC 8441 not enabled).
+      - --entrypoints.websecure.http2.maxConcurrentStreams=0
       # Dev: Traefik default certificate (browser warning expected on localhost).
       - --api.dashboard=true
       - --api.insecure=true