Fix Elements running status after startup

[ekulkisnek]

What changed

• fall back to the orchestrator's ListBinaries status when a managed binary has no dedicated Flutter RPC connection
• use that status for connected, initializing, stopping, and connection-error state

Why

The Elements sidechain is represented by LiquidSignet, which is managed by orchestratord but has no dedicated RPCConnection. BinaryProvider therefore always reported it as disconnected even after orchestratord successfully launched elementsd, leaving the sidechains page on Start.

With this change, the Elements row follows the orchestrator's actual process status and changes to Launching… and then Stop after startup.

Validation

• dart format completed successfully
• git diff --check passed
• confirmed the change is limited to sail_ui/lib/providers/binaries/binary_provider.dart

Per request, no test was added.