Add required_shell_class() to OrgCommands trait with Application
default (backward compatible). GSH dispatch checks session ShellClass
against command requirement before execution.
- ShellClass enum (local, lightweight — avoids bascule-core dep)
- SessionContext enriched with shell_class and posture_level
- Clear error on insufficient shell class directs operator to
reconnect via attested host for System access
- All existing commands work unchanged (Application default)
Signed-off-by: Tyler King <tking@guildhouse.dev>
Signed-off-by: Tyler J King <tking727@gmail.com>