Play Framework

docs(ja): rewrite deployment.textile to match Netty-only English (PF-90)

The Japanese page still described the pre-1.12 world: WAR packaging,
JBoss/WebSphere/Glassfish/Tomcat/Jetty deployment, web.xml editing,
'play war' invocation. The English version was rewritten when this
fork dropped servlet support — JA was missed.

Ports the current English deployment.textile section-for-section:
standalone Netty, start/stop semantics, log tailing, JVM tuning,
the precompiled (no-source) deploy flow, the reverse-proxy
section (TLS termination patterns, path-prefix rewriting, nginx
example, WebSocket pass-through, PaaS PORT handling), and the
systemd unit template. Anchor IDs (standalone, precompiled,
reverseproxy, upstart) match English so cross-page links keep
resolving.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>