Clean up logging in controller and wrap errors

[yushan8]

• Removed redundant logger.Error calls where the error was already being returned
• Replaced common.WithReason with fmt.Errorf wrapping in getchangedtargets.go.
• Promoted cache read failures and corrupt blob warnings from logger.Warn + silent fallthrough to hard errors in getchangedtargets.go.
• Propagated cachedReader.Close() errors instead of ignoring them.
• Made ws.Release() errors in native_orchestrator.go surface via multierr.Append instead of being swallowed.
• Fixed tests to match the new error wrapping.