chore: drop label comments across scripts

CommentsSayWhy read three scripts while 22 comments in 13 other files
named the next statement. They are removed or replaced by the reason,
and the test reads every tracked script and install.py.

scripts/common.py

@@ -263,7 +263,6 @@ def load_platform_config(platform_name: str, platforms_dir: str = "platforms") -
 
     config, chain = _inherited_yaml(platform_name, platforms_dir)
 
-    # Resolve shared group includes
     shared_path = os.path.join(platforms_dir, "_shared.yml")
     # Merge metadata from _registry.yml. The registry is our curated source,
     # while the scraped YAML may be incomplete (missing cores, metadata fields).