Enhance README.md with usage instructions for htpyuikit CLI and add docstring to list command in cli.py for better clarity.

Author: dakixr

README.md

@@ -28,6 +28,23 @@
 - **Add all**: `htpyuikit add --all --dest ./components`
 - **Theme**: `htpyuikit add-theme --dest ./styles/htpy-uikit.css`
 
+```
+Usage: htpyuikit [OPTIONS] COMMAND [ARGS]...
+
+  htpy-uikit CLI: list and scaffold components into your app.
+
+Options:
+  --version   Show the version and exit.
+  -h, --help  Show this message and exit.
+
+Commands:
+  add        Copy one or more components into your app (with deps).
+  add-theme  Copy a theme CSS file into your app.
+  list       List available components.
+  themes     List available themes.
+```
+
+
 ## Config (pyproject.toml)
 
 ```toml

src/htpy_uikit/cli.py

@@ -151,6 +151,7 @@ def cli() -> None:
 
 @cli.command("list")
 def list_cmd() -> None:
+    """List available components."""
     comps = list_components()
     if not comps:
         click.echo("No components found.")