…eaming

- Add GetServiceLogs function to retrieve logs from all running service tasks
- Implement TailServiceLogs using AWS StartLiveTail API for real-time streaming
- Add 5-minute default time window for log retrieval to improve performance
- Support log stream prefix patterns to automatically capture all task streams
- Add proper AWS account ID resolution using STS for StartLiveTail ARN requirements
- Integrate CloudWatch Logs types and STS client in AWSClients structure

This provides both one-shot log viewing and real-time log tailing capabilities
for ECS services, replacing inefficient polling with proper streaming.

…usability

- Extract core CloudWatch log streaming logic into TailLogGroups function
- Keep TailServiceLogs as wrapper handling ECS-specific logic
- Remove unused ServiceName field from ExecuteResult struct
- Fix compilation issues in cmd/run.go and execute.go
- Improve separation of concerns and code reusability

…pletion

- Replace polling-based log retrieval with real-time streaming
- Use TailLogGroups for more efficient CloudWatch API usage
- Add goroutine for concurrent log collection while monitoring task status
- Improve user experience with real-time log output
- Add informative message about CTRL+C behavior
- Remove redundant service loading message from run command

Remove separate getTaskLogs function since it was only used in one place.
Merge the logic directly into GetServiceLogs to reduce complexity and
eliminate unnecessary function overhead.

- Remove 52 lines of code by eliminating getTaskLogs function
- Inline log filtering logic directly in GetServiceLogs task loop
- Preserve identical functionality and error handling
- Improve code maintainability with single-purpose function

- Extract partition from caller's ARN to handle aws-cn, aws-us-gov partitions
- Create dedicated arn.go with partition-aware ARN utilities
- Replace hardcoded "aws" partition with dynamic extraction
- Ensure compatibility across all AWS regions and partitions

- Add comprehensive logs section describing CloudWatch integration
- Include examples for both basic and follow mode usage
- Document automatic log stream discovery and chronological display