Update Docsy to main (pre-0.17.0)

[chalin]

• Theme pin: moves to the docsy main tip pseudo-version (36f73a06); there are no theme/ changes since the previous 54b561dc pin, so this is a metadata-only move.
• Release staging: once v0.17.0 is tagged, a follow-up commit moves the pin to the tag and sets the site version identity (manifest, site-info badge) to 0.17.0; the PR title flips to "Release 0.17.0" then.