A demo build can claim a real shop instead of running on its own

The first demo sealed the office cameras into the package and ran the
PC standalone - a copy of the product with no head office. The bundle
can now carry an installation code instead: setup redeems it exactly as
the app's Setup screen does, the PC joins the shop, and its cameras
arrive from head office on the first sync. The demo then IS the product
- login, Loya, head office - not a local imitation of it. The code is
single-use, so one bundle is one install. release.sh ships the bundle
with DEMO_PACK=.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01KGcjxF1cNLcuwc3DAPcnfj

release.sh

@@ -3,6 +3,10 @@
 #
 #   ./release.sh v0.4.2                 build dist/Behavision-v0.4.2-windows-x64.zip and publish
 #   PUBLISH=0 ./release.sh v0.4.2       build only
+#   DEMO_PACK=demo-cameras.enc ./release.sh v0.4.4-demo
+#                                       a demo build: the sealed bundle from
+#                                       behavision-demo-pack ships in engine-src,
+#                                       and setup asks for its unlock code
 #
 # The package is a SOURCE install: the Go binaries are cross-compiled here, the
 # engine ships as a pure-Python wheel and behavision-setup.exe builds a venv on
@@ -46,6 +50,10 @@ cp pyproject.toml requirements.txt "$STAGE/engine-src/"
 mkdir -p "$STAGE/engine-src/config" && cp config/default.yaml "$STAGE/engine-src/config/"
 rsync -a --exclude '__pycache__' behavision/ "$STAGE/engine-src/behavision/"
 cp installer/INSTALL.txt installer/run-with-lan-head-office.cmd "$STAGE/"
+if [ -n "${DEMO_PACK:-}" ]; then
+  case "$TAG" in *-demo*) ;; *) echo "a DEMO_PACK build must be tagged -demo" >&2; exit 1;; esac
+  cp "$DEMO_PACK" "$STAGE/engine-src/demo-cameras.enc" && echo "   demo bundle: $(basename "$DEMO_PACK")"
+fi
 
 step "4. Package"
 rm -f "$ZIP" && (cd dist && zip -qr "$(basename "$ZIP")" Behavision) && ls -la "$ZIP" | awk '{print "   " $5 " bytes  " $9}'