Speed up scratch image builds with publish-first contexts

docs/INSTALL_GUIDE.md

@@ -55,11 +55,19 @@ The scripts will:
 3. Copy `env/stellaops.env.example` to `.env` if needed (works out of the box)
 4. Start infrastructure and wait for healthy containers
 5. Create or reuse the external frontdoor Docker network from `.env` (`FRONTDOOR_NETWORK`, default `stellaops_frontdoor`)
-6. Build .NET solutions and Docker images
+6. Build repo-owned .NET solutions, then publish backend services locally into small Docker contexts before building hardened runtime images (vendored dependency trees such as `node_modules` are excluded)
 7. Launch the full platform with health checks
 
 Open **https://stella-ops.local** when setup completes.
 
+For targeted backend rebuilds after a scoped code change on Windows:
+
+```powershell
+.\devops\docker\build-all.ps1 -Services notify-web,orchestrator
+```
+
+This path avoids re-sending the full monorepo to Docker for every .NET service image.
+
 ## Manual path (step by step)
 
 ### 1. Environment file