check_library_data's platform filter raises IncompatiblePlatform (an
InvalidLibrary subclass) so the arduino backend branches on the type
instead of substring-matching the message. The {"Wire": "*"} dict
shorthand resolves to the bundled library like PIO's
process_dependencies instead of a registry lookup. libArchive parses
booleans and true/false strings and warns on anything else (bool(str)
made "false" archive). A declared-but-falsy srcDir raises instead of
silently probing. The converter-drop warning names the missing requests,
and the bundled-walk comment states what PIO actually does.