What constitutes a hidden bike path in urban planning, and how can cyclists effectively utilize GIS mapping and local government resources to uncover these routes, which are often intentionally left off of official cycling maps and guides, and what role do you think advocacy groups and cycling organizations play in promoting awareness of these routes and pushing for their inclusion in official city planning documents, and do you believe that these efforts are undermined by the lack of standardization in bike path classification and signage, which can make it difficult for cyclists to identify and access these routes, even when they are made aware of their existence, and what steps can be taken to address this issue and ensure that hidden bike paths are integrated into the broader cycling infrastructure of a city.