Chroot Listener Docs (#22503)

* Chroot Listener Docs

* Update website/content/docs/configuration/listener/tcp.mdx

Co-authored-by: Nick Cabatoff <ncabatoff@hashicorp.com>

* Update website/content/docs/configuration/listener/tcp.mdx

Co-authored-by: Nick Cabatoff <ncabatoff@hashicorp.com>

Update website/content/docs/configuration/listener/tcp.mdx

Co-authored-by: Nick Cabatoff <ncabatoff@hashicorp.com>

Added a statement on what happens when namespace does not exist

* Information on what will happen if a namespace is provided through the CLI or the header

* Changed from specified value to default value

* Edit typo

* Edited docs with clarification on appending

* Edited docs

* Update website/content/docs/configuration/listener/tcp.mdx

Co-authored-by: Sarah Chavis <62406755+schavis@users.noreply.github.com>

---------

Co-authored-by: Nick Cabatoff <ncabatoff@hashicorp.com>
Co-authored-by: Sarah Chavis <62406755+schavis@users.noreply.github.com>

website/content/docs/configuration/listener/tcp.mdx

@@ -62,6 +62,14 @@ default value in the `"/sys/config/ui"` [API endpoint](/vault/api-docs/system/co
   [go-sockaddr template](https://pkg.go.dev/github.com/hashicorp/go-sockaddr/template)
   that is resolved at runtime.
 
+- `chroot_namespace` `(string: "")` – Specifies an alternate top-level namespace
+  for the listener. Vault appends namespaces provided in the `X-Vault-Namespace`
+  header or the `-namespace` field in a CLI command to the top-level namespace
+  to determine the full namespace path for the request. For example, if
+  `chroot_namespace` is set to `admin` and the `X-Vault-Namespace` header is
+  `ns1`, the full namespace path is `admin/ns1`. Calls to the listener will fail
+   with a 4XX error if the top-level namespace provided for `chroot_namespace`
+   does not exist.
 - `http_idle_timeout` `(string: "5m")` - Specifies the maximum amount of time to
   wait for the next request when keep-alives are enabled. If `http_idle_timeout`
   is zero, the value of `http_read_timeout` is used. If both are zero, the value