docs: clean up cmd readme, add just install hint

README.md

@@ -65,7 +65,7 @@ The codebase follows standard Go project layout conventions.
 
 ## Getting started
 
-Requires Go `1.25+`, Bun, and a Playback proxy secret.
+Requires Go `1.25+`, Bun, and [just](https://github.com/casey/just) (`brew install just`).
 
 ```bash
 git clone https://github.com/mkelvers/mal.git && cd mal

cmd/README.md

@@ -1,9 +1,8 @@
 # cmd
 
-Executable entrypoints live here.
+Executables live here.
 
-- `cmd/server`: main web process (`go run ./cmd/server`)
-
-## Why this structure
-
-I wanted to keep the repository root clean and focused on project metadata like `README.md`, `go.mod`, and `Dockerfile`. Keeping entrypoints under `cmd/` also makes it easy to add more binaries later without cluttering the root, and it matches standard Go conventions for projects that grow beyond a single binary.
+| binary | purpose |
+| --- | --- |
+| `cmd/server` | web server |
+| `cmd/user` | user creation CLI |