improvement: exp backoff for container on failure

[spaghettic0de]

Addresses #60

[Copilot]

Pull Request Overview

This PR implements exponential backoff for restarting containers after failures in the Docker service.

• Adds constants for initial and maximum backoff durations
• Introduces exponential backoff logic that increases wait time based on consecutive failure count
• Resets the failure counter when a container starts successfully

[Copilot]

The branch that checks 'if elapsed < backoff_seconds' only logs a message without delaying the loop. Consider introducing an asynchronous sleep (e.g., tokio::time::sleep) to avoid busy waiting.

Suggested change

	Console::info("DockerService", &format!("Waiting before starting new container ({}s remaining)...", backoff_seconds - elapsed));
	let remaining_time = backoff_seconds - elapsed;
	Console::info("DockerService", &format!("Waiting before starting new container ({}s remaining)...", remaining_time));
	sleep(Duration::from_secs(remaining_time as u64)).await;

[JannikSt]

Thanks for your contribution! Can you check the fmt / clippy issue?