deb: retrieve only the artifacts produced by the build, not globbed files

build_binary_package_impl copied the whole parent directory into the
build root (ensure_available) and then retrieved every *.deb / *.changes
/ *.buildinfo it found there. That surfaced stale files already sitting
next to the package tree in the "Built in Ns:" summary.

Now local::build returns the exact set of artifacts produced by this
build — the binary packages registered in debian/files plus the
generated .buildinfo/.changes from generate_binary_metadata — and
build_binary_package_impl retrieves that list instead of globbing the
build root. Only files genuinely produced by the current build are
printed.

src/deb/mod.rs

@@ -17,10 +17,13 @@ pub enum BuildMode {
 
 /// Build package in 'cwd' to a .deb
 ///
-/// Returns the list of produced .deb files retrieved locally. When `ui` is
+/// Returns the list of produced artifacts (.deb files plus the upload
+/// metadata `.buildinfo`/`.changes`) retrieved locally, identified from
+/// `debian/files` and the native metadata generation rather than by
+/// globbing the build root (which would surface stale files). When `ui` is
 /// set, a live view (status bar + rolling log pane) is displayed and all
-/// subprocess output is captured through it; on failure the widget is cleared
-/// and a summary of captured errors is printed.
+/// subprocess output is captured through it; on failure the widget is
+/// cleared and a summary of captured errors is printed.
 #[allow(clippy::too_many_arguments)]
 pub async fn build_binary_package(
     arch: Option<&str>,
@@ -148,8 +151,11 @@ async fn build_binary_package_impl(
             .ok_or("Cannot find parent directory name")?;
         let build_root = format!("{}/{}", build_root, parent_dir_name.to_str().unwrap());
 
-        // Run the build using target build mode
-        match mode {
+        // Run the build using target build mode. It returns the exact set of
+        // artifacts produced by this build (binary packages registered in
+        // debian/files plus the generated .buildinfo/.changes), as paths
+        // inside the build context.
+        let remote_files: Vec<PathBuf> = match mode {
             BuildMode::Local => {
                 local::build(
                     &package,
@@ -167,30 +173,20 @@ async fn build_binary_package_impl(
                 )
                 .await?
             }
-        }
+        };
 
-        // Retrieve produced artifacts (.deb files plus the upload metadata
-        // (.buildinfo/.changes) generated natively after the build)
+        // Retrieve the produced artifacts (binary packages plus the upload
+        // metadata) to the parent directory.
         if let Some(u) = ui {
             u.phase(Phase::RetrievingArtifacts);
         }
-        let remote_files = build_ctx.list_files(Path::new(&build_root))?;
-        let deb_files: Vec<PathBuf> = remote_files
-            .into_iter()
-            .filter(|f| {
-                f.extension().is_some_and(|ext| {
-                    matches!(
-                        ext.to_str(),
-                        Some("deb") | Some("buildinfo") | Some("changes")
-                    )
-                })
-            })
-            .collect();
-        let total_debs = deb_files.len();
+        let total_debs = remote_files.len();
 
         let mut artifacts = Vec::with_capacity(total_debs);
-        for (idx, remote_file) in deb_files.iter().enumerate() {
-            let file_name = remote_file.file_name().ok_or("Invalid remote filename")?;
+        for (idx, remote_file) in remote_files.iter().enumerate() {
+            let file_name = remote_file
+                .file_name()
+                .ok_or("Invalid remote filename")?;
             let local_dest = parent_dir.join(file_name);
             build_ctx.retrieve_path(remote_file, &local_dest)?;
             artifacts.push(local_dest);