fix(packaging): move templates/ into decnet/ package so they ship with pip install

The docker build contexts and syslog_bridge.py lived at repo root, which
meant setuptools (include = ["decnet*"]) never shipped them. Agents
installed via `pip install $RELEASE_DIR` got site-packages/decnet/** but no
templates/, so every deploy blew up in deployer._sync_logging_helper with
FileNotFoundError on templates/syslog_bridge.py.

Move templates/ -> decnet/templates/ and declare it as setuptools
package-data. Path resolutions in services/*.py and engine/deployer.py drop
one .parent since templates now lives beside the code. Test fixtures,
bandit exclude path, and coverage omit glob updated to match.

decnet/templates/ssh/Dockerfile

@@ -0,0 +1,116 @@
+ARG BASE_IMAGE=debian:bookworm-slim
+FROM ${BASE_IMAGE}
+
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    openssh-server \
+    sudo \
+    rsyslog \
+    curl \
+    wget \
+    vim \
+    nano \
+    net-tools \
+    procps \
+    htop \
+    git \
+    inotify-tools \
+    psmisc \
+    iproute2 \
+    iputils-ping \
+    ca-certificates \
+    nmap \
+    jq \
+    python3 \
+    && rm -rf /var/lib/apt/lists/*
+
+RUN mkdir -p /var/run/sshd /root/.ssh /var/log/journal /var/lib/systemd/coredump \
+    && chmod 700 /var/lib/systemd/coredump
+
+# sshd_config: allow root + password auth; VERBOSE so session lines carry
+# client IP + session PID (needed for file-capture attribution).
+RUN sed -i \
+    -e 's|^#\?PermitRootLogin.*|PermitRootLogin yes|' \
+    -e 's|^#\?PasswordAuthentication.*|PasswordAuthentication yes|' \
+    -e 's|^#\?ChallengeResponseAuthentication.*|ChallengeResponseAuthentication no|' \
+    -e 's|^#\?LogLevel.*|LogLevel VERBOSE|' \
+    /etc/ssh/sshd_config
+
+# rsyslog: forward auth.* and user.* to PID 1's stdout in RFC 5424 format.
+# /proc/1/fd/1 is the container-stdout fd Docker attached — writing there
+# surfaces lines in `docker logs` without needing a named pipe + relay cat
+# (which would be readable AND writable by any root-in-container process).
+RUN printf '%s\n' \
+    '# auth + user events → container stdout as RFC 5424' \
+    '$template RFC5424fmt,"<%PRI%>1 %TIMESTAMP:::date-rfc3339% %HOSTNAME% %APP-NAME% %PROCID% %MSGID% %STRUCTURED-DATA% %msg%\n"' \
+    'auth,authpriv.*  /proc/1/fd/1;RFC5424fmt' \
+    'user.*           /proc/1/fd/1;RFC5424fmt' \
+    > /etc/rsyslog.d/50-journal-forward.conf
+
+# Silence default catch-all rules so we own auth/user routing exclusively.
+# Also disable rsyslog's privilege drop: PID 1's stdout (/proc/1/fd/1) is
+# owned by root, so a syslog-user rsyslogd gets EACCES and silently drops
+# every auth/user line (bash CMD events + file_captured emissions).
+RUN sed -i \
+    -e 's|^\(\*\.\*;auth,authpriv\.none\)|#\1|' \
+    -e 's|^auth,authpriv\.\*|#auth,authpriv.*|' \
+    -e 's|^\$PrivDropToUser|#$PrivDropToUser|' \
+    -e 's|^\$PrivDropToGroup|#$PrivDropToGroup|' \
+    /etc/rsyslog.conf
+
+# Sudo: log to syslog (auth facility) AND a local file with full I/O capture
+RUN echo 'Defaults logfile="/var/log/sudo.log"' >> /etc/sudoers && \
+    echo 'Defaults syslog=auth'                >> /etc/sudoers && \
+    echo 'Defaults log_input,log_output'       >> /etc/sudoers
+
+# Lived-in environment: motd, shell aliases, fake project files
+RUN echo "Ubuntu 22.04.3 LTS" > /etc/issue.net && \
+    echo "Welcome to Ubuntu 22.04.3 LTS (GNU/Linux 5.15.0-88-generic x86_64)" > /etc/motd && \
+    echo "" >> /etc/motd && \
+    echo " * Documentation:  https://help.ubuntu.com" >> /etc/motd && \
+    echo " * Management:     https://landscape.canonical.com" >> /etc/motd && \
+    echo " * Support:        https://ubuntu.com/advantage" >> /etc/motd
+
+RUN echo 'alias ll="ls -alF"' >> /root/.bashrc && \
+    echo 'alias la="ls -A"'   >> /root/.bashrc && \
+    echo 'alias l="ls -CF"'   >> /root/.bashrc && \
+    echo 'export HISTSIZE=1000' >> /root/.bashrc && \
+    echo 'export HISTFILESIZE=2000' >> /root/.bashrc && \
+    echo 'PROMPT_COMMAND='"'"'logger -p user.info -t bash "CMD uid=$UID user=$USER src=${SSH_CLIENT%% *} pwd=$PWD cmd=$(history 1 | sed "s/^ *[0-9]* *//")";'"'" >> /root/.bashrc
+
+# Fake project files to look lived-in
+RUN mkdir -p /root/projects /root/backups /var/www/html && \
+    printf '# TODO: migrate DB to new server\n# check cron jobs\n# update SSL cert\n' > /root/notes.txt && \
+    printf 'DB_HOST=10.0.0.5\nDB_USER=admin\nDB_PASS=changeme123\nDB_NAME=prod_db\n' > /root/projects/.env && \
+    printf '[Unit]\nDescription=App Server\n[Service]\nExecStart=/usr/bin/python3 /opt/app/server.py\n' > /root/projects/app.service
+
+# Stage all capture sources in a scratch dir. Nothing here survives the layer:
+# _build_stealth.py packs syslog_bridge.py + emit_capture.py + capture.sh into
+# XOR+gzip+base64 blobs embedded directly in /entrypoint.sh, and the whole
+# /tmp/build tree is wiped at the end of the RUN — so the final image has no
+# `.py` file under /opt and no `journal-relay` script under /usr/libexec/udev.
+COPY entrypoint.sh capture.sh syslog_bridge.py emit_capture.py \
+     argv_zap.c _build_stealth.py /tmp/build/
+
+# argv_zap is compiled into a shared object disguised as a multiarch
+# udev-companion library (sits next to real libudev.so.1). gcc is installed
+# only for this build step and purged in the same layer.
+RUN set -eu \
+    && apt-get update \
+    && apt-get install -y --no-install-recommends gcc libc6-dev \
+    && mkdir -p /usr/lib/x86_64-linux-gnu /usr/libexec/udev \
+    && gcc -O2 -fPIC -shared \
+        -o /usr/lib/x86_64-linux-gnu/libudev-shared.so.1 \
+        /tmp/build/argv_zap.c -ldl \
+    && apt-get purge -y gcc libc6-dev \
+    && apt-get autoremove -y \
+    && rm -rf /var/lib/apt/lists/* \
+    && ln -sf /usr/bin/inotifywait /usr/libexec/udev/kmsg-watch \
+    && python3 /tmp/build/_build_stealth.py \
+    && rm -rf /tmp/build
+
+EXPOSE 22
+
+HEALTHCHECK --interval=30s --timeout=5s --start-period=10s --retries=3 \
+  CMD kill -0 1 || exit 1
+
+ENTRYPOINT ["/entrypoint.sh"]