Disable ANSI colors in logs and fix fail2ban regex

- Add with_ansi(false) to all tracing_subscriber fmt layers so log
  output (both stdout and file) is plain text without escape codes.
  This is critical for Docker deployments and fail2ban log parsing.

- Remove ^ anchor from fail2ban failregex since log lines have a
  timestamp/level prefix before RATE_LIMIT.

deploy/fail2ban/filter.d/reverse-proxy.conf

@@ -1,3 +1,3 @@
 [Definition]
-failregex = ^RATE_LIMIT client_ip=<HOST> host=\S+ path=\S+ status=\d+$
+failregex = RATE_LIMIT client_ip=<HOST> host=\S+ path=\S+ status=\d+
 ignoreregex =