feat: supply drop version during release build

Dockerfile

@@ -1,3 +1,5 @@
+# syntax=docker/dockerfile:1
+
 # Unified deps builder
 FROM node:lts-alpine AS deps
 WORKDIR /app
@@ -12,10 +14,15 @@ WORKDIR /app
 ENV NODE_ENV=production
 ENV NUXT_TELEMETRY_DISABLED=1
 
+# add git so drop can determine its git ref at build
+RUN apk add git
+
 # copy deps and rest of project files
 COPY --from=deps /app/node_modules ./node_modules
 COPY . .
 
+ARG BUILD_DROP_VERSION="v0.0.0-unknown.1"
+
 # build
 RUN yarn postinstall
 RUN yarn build