Provider registry silently drops docs/functions/ — provider-defined functions have no documentation category

The private provider registry ingests only overview, resource and data source documentation. Pages under docs/functions/ — the standard layout emitted by HashiCorp's own tfplugindocs — are discarded on upload with no error or warning, so providers that ship functions have no documentation in the registry UI beyond their overview page.

To reproduce

1. Publish a provider whose docs/ contains index.md and functions/<name>.md

2. spacectl provider upload-docs --version <id> --docs-archive docs.tgz → exits 0

3. Query docs { files { key type } } → only docs/index.md is present