docs: add alias --save flag
# alias
-This command allows you to define shortcuts for other common commands.
+This command allows you to define shortcuts for other common commands. By default, they only apply to the current session. To persist them, add `--save`.
+
+Syntax: `alias {flags} <name> [<parameters>] {<body>}`
The command expects three parameters:
* the name of alias
* the parameters as a space-separated list (`[a b ...]`), can be empty (`[]`)
* the body of the alias as a `{...}` block
+## Flags
+
+* `-s`, `--save`: Save the alias to your config (see `config --path` to edit them later)
+
## Examples
Define a custom `myecho` command as an alias:
