fix(cookbook): copy path source in fetch_offline() too (was only in fetch())

fetch_offline() is called for protected recipes (base, kernel, relibc, etc.)
when REDBEAR_ALLOW_PROTECTED_FETCH=1 is set. Previously, its Path source
arm called only redbear_ensure_offline_source() which fails with
'is not exist' if the source dir is empty.

The fix: do the same copy_dir_all() in fetch_offline()'s Path arm as
in fetch()'s Path arm. This means local fork paths (local/sources/base,
local/sources/relibc, etc.) are correctly copied into recipes/<name>/source
during protected recipe fetch.

src/cook/fetch.rs

@@ -354,10 +354,23 @@ pub fn fetch_offline(recipe: &CookRecipe, logger: &PtyOut) -> Result<FetchResult
     }
 
     let result = match &recipe.recipe.source {
-        Some(SourceRecipe::Path { path: _ }) => {
-            redbear_ensure_offline_source(recipe_dir, &source_dir, logger)?;
-            let ident = fetch_apply_source_info(recipe, "".to_string())?;
-            FetchResult::cached(source_dir, ident)
+        Some(SourceRecipe::Path { path }) => {
+            let path = recipe_dir.join(path);
+            let cached = source_dir.is_dir() && modified_dir(&path)? <= modified_dir(&source_dir)?;
+            if !cached {
+                log_to_pty!(
+                    logger,
+                    "[DEBUG]: {:?} is newer than {:?}",
+                    path.display(),
+                    source_dir.display()
+                );
+                copy_dir_all(&path, &source_dir).map_err(wrap_io_err!(
+                    &path,
+                    source_dir,
+                    "Copying source"
+                ))?;
+            }
+            FetchResult::new(source_dir, "local_source".to_string(), cached)
         }
         None => {
             let ident = fetch_apply_source_info(recipe, "".to_string())?;