Rewrite INTENT.md as the sand-boxer meta-framework charter (OpenRouter-style
sandbox API, extensions, payments, Coulomb sibling boundaries). Add research
under research/, update SCOPE.md, bootstrap workplans SAND-WP-0001/0002, and
State Hub integration files from the bootstrap pass.
Charter the repo as Custodian execution isolation: sandbox profiles,
dedicated hosts (sandboxer01), and migration path from the-custodian
e2e-framework and build-machines patterns.
