chore: update nightly docs

[github-actions]

This is an automated PR to update the nightly docs.

[cursor]

PR Summary

Low Risk
Documentation-only submodule pointer bumps with no auth, payment, or core product logic changes.

Overview
Automated nightly docs sync — this PR refreshes the docs hub’s nightly documentation snapshots so the site tracks the latest upstream content.

Per the scheduled update-nightly workflow, it runs pnpm docs:update:nightly to advance git submodule checkouts under docs/nightly/ (e.g. specs, SDK docs, sway, and other linked repos) and commit those pointer updates. No application runtime code is intended to change—only which commits the nightly doc submodules reference.

^{Reviewed by Cursor Bugbot for commit 657a752. Bugbot is set up for automated code reviews on this repo. Configure here.}