fix(status): Address review findings from code review
- Replace tuple with TypeBreakdown struct for Sendable conformance
- Narrow catch to CLIError.notInitialized to avoid swallowing future cases
- Single dictionary lookup in computeBackupStats
- Hoist NumberFormatter to file-level constant
- Avoid intermediate array in computeS3Info via max(by:)
- Fix typo in test name (s3InfoDerives)