Avoid panic in profile directory walk

Replace an internal expect() in the installer walkdir path handling

with a structured IO error to keep failure behavior recoverable.

Author: jasantunes

src/profiles/installer.rs

@@ -293,9 +293,13 @@ fn copy_directory_contents(
     for entry in WalkDir::new(source_dir).follow_links(true) {
         let entry = entry.map_err(|e| ProfileError::IoError(std::io::Error::other(e)))?;
         let entry_path = entry.path();
-        let relative = entry_path
-            .strip_prefix(source_dir)
-            .expect("walkdir entry should be under source_dir");
+        let relative = entry_path.strip_prefix(source_dir).map_err(|_| {
+            ProfileError::IoError(std::io::Error::other(format!(
+                "walkdir entry '{}' is outside source '{}'",
+                entry_path.display(),
+                source_dir.display()
+            )))
+        })?;
 
         if relative.as_os_str().is_empty() {
             continue;