refactor: strip DECNET tokens from container-visible surface

Rename the container-side logging module decnet_logging → syslog_bridge
(canonical at templates/syslog_bridge.py, synced into each template by
the deployer). Drop the stale per-template copies; setuptools find was
picking them up anyway. Swap useradd/USER/chown "decnet" for "logrelay"
so no obvious token appears in the rendered container image.

Apply the same cloaking pattern to the telnet template that SSH got:
syslog pipe moves to /run/systemd/journal/syslog-relay and the relay
is cat'd via exec -a "systemd-journal-fwd". rsyslog.d conf rename
99-decnet.conf → 50-journal-forward.conf. SSH capture script:
/var/decnet/captured → /var/lib/systemd/coredump (real systemd path),
logger tag decnet-capture → systemd-journal. Compose volume updated
to match the new in-container quarantine path.

SD element ID shifts decnet@55555 → relay@55555; synced across
collector, parser, sniffer, prober, formatter, tests, and docs so the
host-side pipeline still matches what containers emit.

templates/conpot/Dockerfile

@@ -11,16 +11,16 @@ RUN find /opt /usr /etc /home -name "*.xml" -exec sed -i 's/port="5020"/port="50
 RUN (apt-get update && apt-get install -y --no-install-recommends libcap2-bin 2>/dev/null) || (apk add --no-cache libcap 2>/dev/null) || true
 RUN find /home/conpot/.local/bin /usr /opt -type f -name 'python*' -exec setcap 'cap_net_bind_service+eip' {} \; 2>/dev/null || true
 
-# Bridge conpot's own logger into DECNET's RFC 5424 syslog pipeline.
+# Bridge conpot's own logger into syslog-relay's RFC 5424 syslog pipeline.
 # entrypoint.py is self-contained (inlines the formatter) because the
 # conpot base image runs Python 3.6, which cannot import the shared
-# decnet_logging.py (that file uses 3.9+ / 3.10+ type syntax).
+# syslog_bridge.py (that file uses 3.9+ / 3.10+ type syntax).
 COPY entrypoint.py /home/conpot/entrypoint.py
 RUN chown conpot:conpot /home/conpot/entrypoint.py \
     && chmod +x /home/conpot/entrypoint.py
 
 # The upstream image already runs as non-root 'conpot'.
-# We do NOT switch to a 'decnet' user — doing so breaks pkg_resources
+# We do NOT switch to a 'logrelay' user — doing so breaks pkg_resources
 # because conpot's eggs live under /home/conpot/.local and are only on
 # the Python path for that user.
 USER conpot

templates/conpot/decnet_logging.py

@@ -1,89 +0,0 @@
-#!/usr/bin/env python3
-"""
-Shared RFC 5424 syslog helper for DECNET service templates.
-
-Services call syslog_line() to format an RFC 5424 message, then
-write_syslog_file() to emit it to stdout — Docker captures it, and the
-host-side collector streams it into the log file.
-
-RFC 5424 structure:
-  <PRI>1 TIMESTAMP HOSTNAME APP-NAME PROCID MSGID [SD-ELEMENT] MSG
-
-Facility: local0 (16), PEN for SD element ID: decnet@55555
-"""
-
-from datetime import datetime, timezone
-from typing import Any
-
-# ─── Constants ────────────────────────────────────────────────────────────────
-
-_FACILITY_LOCAL0 = 16
-_SD_ID = "decnet@55555"
-_NILVALUE = "-"
-
-SEVERITY_EMERG   = 0
-SEVERITY_ALERT   = 1
-SEVERITY_CRIT    = 2
-SEVERITY_ERROR   = 3
-SEVERITY_WARNING = 4
-SEVERITY_NOTICE  = 5
-SEVERITY_INFO    = 6
-SEVERITY_DEBUG   = 7
-
-_MAX_HOSTNAME = 255
-_MAX_APPNAME  = 48
-_MAX_MSGID    = 32
-
-# ─── Formatter ────────────────────────────────────────────────────────────────
-
-def _sd_escape(value: str) -> str:
-    """Escape SD-PARAM-VALUE per RFC 5424 §6.3.3."""
-    return value.replace("\\", "\\\\").replace('"', '\\"').replace("]", "\\]")
-
-
-def _sd_element(fields: dict[str, Any]) -> str:
-    if not fields:
-        return _NILVALUE
-    params = " ".join(f'{k}="{_sd_escape(str(v))}"' for k, v in fields.items())
-    return f"[{_SD_ID} {params}]"
-
-
-def syslog_line(
-    service: str,
-    hostname: str,
-    event_type: str,
-    severity: int = SEVERITY_INFO,
-    timestamp: datetime | None = None,
-    msg: str | None = None,
-    **fields: Any,
-) -> str:
-    """
-    Return a single RFC 5424-compliant syslog line (no trailing newline).
-
-    Args:
-        service:    APP-NAME (e.g. "http", "mysql")
-        hostname:   HOSTNAME (decky node name)
-        event_type: MSGID    (e.g. "request", "login_attempt")
-        severity:   Syslog severity integer (default: INFO=6)
-        timestamp:  UTC datetime; defaults to now
-        msg:        Optional free-text MSG
-        **fields:   Encoded as structured data params
-    """
-    pri     = f"<{_FACILITY_LOCAL0 * 8 + severity}>"
-    ts      = (timestamp or datetime.now(timezone.utc)).isoformat()
-    host    = (hostname or _NILVALUE)[:_MAX_HOSTNAME]
-    appname = (service  or _NILVALUE)[:_MAX_APPNAME]
-    msgid   = (event_type or _NILVALUE)[:_MAX_MSGID]
-    sd      = _sd_element(fields)
-    message = f" {msg}" if msg else ""
-    return f"{pri}1 {ts} {host} {appname} {_NILVALUE} {msgid} {sd}{message}"
-
-
-def write_syslog_file(line: str) -> None:
-    """Emit a syslog line to stdout for Docker log capture."""
-    print(line, flush=True)
-
-
-def forward_syslog(line: str, log_target: str) -> None:
-    """No-op stub. TCP forwarding is now handled by rsyslog, not by service containers."""
-    pass

templates/conpot/entrypoint.py

@@ -3,7 +3,7 @@
 Entrypoint wrapper for the Conpot ICS/SCADA honeypot.
 
 Launches conpot as a child process and bridges its log output into the
-DECNET structured syslog pipeline.  Each line from conpot stdout/stderr
+syslog-relay structured syslog pipeline.  Each line from conpot stdout/stderr
 is classified and emitted as an RFC 5424 syslog line so the host-side
 collector can ingest it alongside every other service.
 
@@ -21,7 +21,7 @@ from datetime import datetime, timezone
 # ── RFC 5424 inline formatter (Python 3.6-compatible) ─────────────────────────
 
 _FACILITY_LOCAL0 = 16
-_SD_ID = "decnet@55555"
+_SD_ID = "relay@55555"
 _NILVALUE = "-"
 
 SEVERITY_INFO    = 6