`claw /status`, `claw /diff`, `claw /version`, `claw /doctor`,
`claw /sandbox` all returned interactive_only because the direct-slash
handler only had explicit arms for /help, /agents, /mcp, /skills.
Other resume-safe slash commands fell through to the generic
`Ok(Some(command)) => Err(interactive_only...)` arm.
Fix: add explicit routing arms for SlashCommand::Status, ::Diff,
::Version, ::Doctor, ::Sandbox in `parse_direct_slash_command`.
One new integration test: direct_slash_resume_safe_commands_route_correctly
(covers /version, /sandbox, /diff)
572+ tests pass.