[PATCH datacenter-manager] ui: auto-installer: improve auto-installer command line template

[Christian Ebner <c.ebner@proxmox.com>]

The auto-generated command line for the auto-installer to be copied
by an user needs to be adapted to include the source image. An
unexpecting user might just copy the command and past it, running
into a not so telling: `Error: free-standing argument is missing`.

Make it clearer that this is a template only and add a template input
file, which leads to the following more telling error messages on
missing or unrelated input files:
- `Error: Source file "SOURCE-INPUT-FILE" does not exist.`
- `Error: The source ISO file is not able to be installed automatically.
  Please try a more current one.`

Signed-off-by: Christian Ebner <c.ebner@proxmox.com>
---
 ui/src/remotes/auto_installer/prepared_answer_form.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/ui/src/remotes/auto_installer/prepared_answer_form.rs b/ui/src/remotes/auto_installer/prepared_answer_form.rs
index c1d2bab..15be027 100644
--- a/ui/src/remotes/auto_installer/prepared_answer_form.rs
+++ b/ui/src/remotes/auto_installer/prepared_answer_form.rs
@@ -933,7 +933,7 @@ pub fn render_show_secret_dialog(
         pdm_origin().unwrap_or_else(|| "https://pdm.example.com:8443".to_owned())
     );
     let commandline = format!(
-        "proxmox-auto-install-assistant prepare-iso --fetch-from http --url {answer_url} --answer-auth-token {token}",
+        "proxmox-auto-install-assistant prepare-iso --fetch-from http --url {answer_url} --answer-auth-token {token} SOURCE-INPUT-FILE",
     );
 
     let copy_commandline_view = Container::new()
@@ -960,7 +960,7 @@ pub fn render_show_secret_dialog(
                                 move |_| copy_text_to_clipboard(&commandline)
                             }),
                     )
-                    .tip(tr!("Copy command line to clipboard.")),
+                    .tip(tr!("Copy template command line to clipboard. Adapt SOURCE-INPUT-FILE to your needs.")),
                 ),
         );
 
-- 
2.47.3