init: initial commit

- ticker / QR ad overlay / break slide graphics (1920×1080) with all
  geometry derived from one shared module (src/shared/obs-geometry.mjs)
- OBS scene-collection generator (scripts/generate-obs-scenes.mjs) and a
  read-only in-dashboard setup verifier, both driven by the same module
- en/sr dashboard i18n selected via bundle config; configschema.json with
  neutral first-run defaults seeded from optional branding config
- install.sh / systemd user service / update.sh for venue deployment
- reference OBS scene collection + profile from a real venue as fixtures

deploy/nodecg-venue-gfx.service

@@ -0,0 +1,19 @@
+# systemd user service for the NodeCG install driving the venue graphics.
+# Installed by scripts/install-service.sh (which fills in the install dir);
+# runs as a *user* service so it shares the session with OBS and never needs
+# root. Remember `loginctl enable-linger <user>` for start-on-boot without a
+# login.
+
+[Unit]
+Description=NodeCG venue graphics (nodecg-venue-gfx)
+After=network-online.target
+
+[Service]
+WorkingDirectory=__INSTALL_DIR__
+ExecStart=/usr/bin/env node index.js
+Restart=always
+RestartSec=5
+Environment=NODE_ENV=production
+
+[Install]
+WantedBy=default.target