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/cowrie/entrypoint.sh

@@ -0,0 +1,33 @@
+#!/bin/bash
+set -e
+
+# Render Jinja2 config template
+/home/cowrie/cowrie-env/bin/python3 - <<'EOF'
+import os
+from jinja2 import Template
+
+with open("/home/cowrie/cowrie.cfg.j2") as f:
+    tpl = Template(f.read())
+
+rendered = tpl.render(**os.environ)
+
+with open("/home/cowrie/cowrie-env/etc/cowrie.cfg", "w") as f:
+    f.write(rendered)
+EOF
+
+# Write userdb.txt if custom users were provided
+# Format: COWRIE_USERDB_ENTRIES=root:toor,admin:admin123
+if [ -n "${COWRIE_USERDB_ENTRIES}" ]; then
+    USERDB="/home/cowrie/cowrie-env/etc/userdb.txt"
+    : > "$USERDB"
+    IFS=',' read -ra PAIRS <<< "${COWRIE_USERDB_ENTRIES}"
+    for pair in "${PAIRS[@]}"; do
+        user="${pair%%:*}"
+        pass="${pair#*:}"
+        uid=1000
+        [ "$user" = "root" ] && uid=0
+        echo "${user}:${uid}:${pass}" >> "$USERDB"
+    done
+fi
+
+exec authbind --deep /home/cowrie/cowrie-env/bin/twistd -n --pidfile= cowrie