Fix restart handoff convergence on main

[peters]

Summary

• Land the restart convergence proof fixes from the side branch onto main.
• Preserve the first supervised child arguments so lifecycle flags can prove the replacement runtime, while restart loops drop one-shot lifecycle flags.
• Mark self-supervised runtimes converged when the active runtime manifest matches the pending target version.
• Accept a running active executable as current only when node-local update status has converged for that version.

Root Cause

The previous main line could leave .surge-update-status.json at pending_restart after the target child was already running. The newest targeted fixes existed on fix/restart-convergence-proof, but the later main beta line did not include them.

Validation

• cargo test -p surge-supervisor handoff
• cargo test -p surge-ffi self_supervisor_converges_pending_status_when_runtime_manifest_matches
• cargo test -p surge-cli build_remote_process_verification_probe
• ./scripts/sync-surge-core-vendor.sh --check
• ./scripts/check-version-sync.sh
• cargo fmt --all -- --check
• RUSTFLAGS="-D warnings" cargo test --workspace
• cargo clippy --all-targets --all-features -- -D warnings
• cargo clippy --workspace --lib --bins --examples -- -D warnings -D clippy::unwrap_used -D clippy::expect_used
• cargo clippy --workspace --all-targets --all-features -- -D warnings -W clippy::pedantic
• dotnet format dotnet/Surge.slnx --verify-no-changes
• dotnet test dotnet/Surge.slnx --configuration Release