add config-driven channel label and dev-workstation bootstrap

A bleeding-edge container running next to a stable one on the same dev box is easy to confuse, and a branch-only badge would force perpetual rebase/cherry-pick drift between main and dev-be. Instead the badge is config-driven: the settings endpoint injects a synthetic env_label from SHOPDB_ENV_LABEL, the sidebar renders a red DEV tag only when it is non-empty, and stable simply leaves it unset. Same code on both channels, no divergence.

dev-bootstrap.ps1 makes a fresh Windows box turnkey: it checks git/Docker (winget-installs with a prompt), verifies the engine is actually running, then builds and starts an isolated per-channel stack so stable and edge coexist on distinct ports, projects, and volumes. docker-compose.channel.yml is a thin overlay so the base compose file stays channel-agnostic.

frontend/src/utils/siteSettings.js

@@ -37,6 +37,14 @@ export async function getFacilityName() {
   return getSetting('facility_name', 'ShopDB')
 }
 
+// Environment channel label (e.g. 'DEV') injected by the backend from
+// SHOPDB_ENV_LABEL. Empty on stable/main deployments, which renders no badge.
+// Drives the red DEV tag in the sidebar so a bleeding-edge container is
+// obviously distinct from a stable one running side by side.
+export async function getEnvLabel() {
+  return getSetting('env_label', '')
+}
+
 // Main site logo (sidebar, login, dashboard header). Fallback = shipped GE mark.
 export async function getSiteLogo() {
   return withBase(await getSetting('site_logo', '/ge-aerospace-logo.svg'))