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/https/entrypoint.sh

@@ -0,0 +1,18 @@
+#!/bin/bash
+set -e
+
+TLS_DIR="/opt/tls"
+CERT="${TLS_CERT:-$TLS_DIR/cert.pem}"
+KEY="${TLS_KEY:-$TLS_DIR/key.pem}"
+
+# Generate a self-signed certificate if none exists
+if [ ! -f "$CERT" ] || [ ! -f "$KEY" ]; then
+    mkdir -p "$TLS_DIR"
+    CN="${TLS_CN:-${NODE_NAME:-localhost}}"
+    openssl req -x509 -newkey rsa:2048 -nodes \
+        -keyout "$KEY" -out "$CERT" \
+        -days 3650 -subj "/CN=$CN" \
+        2>/dev/null
+fi
+
+exec python3 /opt/server.py