Update README.md

Author: juntao

docker/server/README.md

@@ -5,18 +5,32 @@ This directory contains a multi-stage Dockerfile for producing a lean runtime im
 - **Builder stage** (`rust:1.85-slim`): installs the minimal Rust toolchain dependencies, clones `https://github.com/second-state/echokit_server`, and compiles the project in release mode.
 - **Runtime stage** (`debian:bookworm-slim`): installs the required runtime libraries, copies the compiled binary and default `config.toml`, and sets `RUST_LOG=info` before starting the server with that config.
 
+## Run
+
+Mount your local `config.toml` so the container uses your configuration:
+
+```sh
+docker run --rm -p 8080:8080 -v $(pwd)/config.toml:/app/config.toml secondstate/echokit:latest-server
+```
+
+The container executes `echokit_server config.toml` by default, reading logs at the `info` level.
+
 ## Build
 
 ```sh
-docker build -t echokit:latest-server .
+docker build -t secondstate/echokit:latest-server .
 ```
 
-## Run
+## Multi-platform build
 
-Mount your local `config.toml` so the container uses your configuration:
+```sh
+docker buildx build . --platform linux/arm64,linux/amd64 --tag secondstate/echokit:latest-server -f Dockerfile
+```
+
+## Publish 
 
 ```sh
-docker run --rm -v $(pwd)/config.toml:/app/config.toml echokit:latest-server
+docker login
+docker push secondstate/echokit:latest-server
 ```
 
-The container executes `echokit_server config.toml` by default, reading logs at the `info` level.