fix(util/script_state): deadlock

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
fix(kernel/metavar): typo

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
feat(library/kernel_bindings): substitution Lua API

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
feat(library/kernel_bindings): justification Lua API

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>