Migrate build assets and scripts to deploy/docker structure

- Removed `install.sh` and moved Docker-related assets to `deploy/docker`.
- Updated all Dockerfile references from `build/` to `deploy/docker/`.
- Refactored paths in E2E tests, Makefile, and documentation for consistency with new directory structure.
- Added `HAPROXY_STATS_CORS_ORIGIN` environment variable in `docker-compose.yml`.

.github/workflows/build.yml

@@ -201,7 +201,7 @@ jobs:
         uses: docker/build-push-action@v5
         with:
           context: .
-          file: build/Dockerfile
+          file: deploy/docker/Dockerfile
           build-args: |
             RELEASE_VERSION_ARG="${{ steps.tags.outputs.result }}"
           platforms: linux/amd64,linux/arm64