new: build the target-distribution menu from supported_dists

src/distro_info.rs

@@ -214,9 +214,12 @@ fn parse_series_csv(content: &str) -> Result<Vec<SeriesInformation>, Box<dyn Err
     Ok(series_info_list)
 }
 
-/// List the distributions known to pkh (e.g. "debian", "ubuntu")
+/// List the distributions known to pkh (e.g. "debian", "ubuntu"), sorted so
+/// that menus and error messages derived from it are deterministic
 pub fn supported_dists() -> Vec<String> {
-    DATA.dist.keys().cloned().collect()
+    let mut dists: Vec<String> = DATA.dist.keys().cloned().collect();
+    dists.sort();
+    dists
 }
 
 /// Special changelog distribution marking an entry that has not been

src/new/questions.rs

@@ -437,17 +437,26 @@ async fn run_wizard(mut cli: NewCli) -> Result<NewOptions, Box<dyn Error>> {
         cli.maintainer = Some(ask_text("Maintainer", &default, validate)?);
     }
 
-    // 11. Target distribution.
+    // 11. Target distribution. The menu derives from the distro data pkh
+    //     ships (sorted); ubuntu is moved to the front when present so it
+    //     stays the menu's first entry and fallback default as it has always
+    //     been — prompt::select positions on a default value, not an index.
     if cli.dist.is_none() {
         let vendor = crate::build::env::current_vendor().to_lowercase();
-        let options = vec!["ubuntu".to_string(), "debian".to_string()];
+        let mut options = crate::distro_info::supported_dists();
+        if let Some(pos) = options.iter().position(|d| d == "ubuntu")
+            && pos > 0
+        {
+            let ubuntu = options.remove(pos);
+            options.insert(0, ubuntu);
+        }
         let default = if options.contains(&vendor) {
             vendor
         } else {
             "ubuntu".to_string()
         };
         let answer = select_from(DIST_LABEL, &options, &default, |answer| {
-            answer == "ubuntu" || answer == "debian"
+            options.contains(&answer.to_string())
         })?;
         cli.dist = Some(answer);
     }