fix(cloud/submit): remove NUL-containing legacy block from source
- Use program.to_string_lossy().as_ref() to satisfy Option<&str>
- Delete disabled block with NUL to avoid binary heuristics in tools
- Build verified via ./build-fast.sh
- Insert safe loop that formats with '. ' and avoid legacy NUL format
- Wrap legacy loop in to prevent execution
- Keeps earlier final-output sanitizer as an extra guard
- Sanitize submit --wait output by removing embedded NULs before printing
- Adjust executor PATH check to also skip when family==cloud and no custom config
- Builds clean with ./build-fast.sh
- Add cloud submit non-interactive path with optional --wait
- Poll remote status and print final results (messages + diff)
- Stream stderr progress into Agents HUD; cap very large outputs (~500KB)
- Treat 'cloud' as a built-in agent (no external binary needed)
- Wire core agent_run to invoke current executable with cloud submit --wait
Validated via ./build-fast.sh (no warnings).
James Peter