fix(security): prevent integer overflow in uint64 to int64 conversions

Add overflow checks before converting uint64 memory values to int64
to prevent potential integer overflow issues identified by gosec (G115).

- Add math.MaxInt64 checks in fileproc/backpressure.go
- Add math.MaxInt64 checks in fileproc/resource_monitor_validation.go
- Add math.MaxInt64 checks in fileproc/resource_monitor_metrics.go
- Add math.MaxInt64 check in benchmark/benchmark.go with nosec annotation

Co-authored-by: ivuorinen <11024+ivuorinen@users.noreply.github.com>

cli/processor_collection.go

@@ -74,4 +74,4 @@ func (p *Processor) validateFileCollection(files []string) error {
 
 	logrus.Infof("Pre-validation passed: %d files, %d MB total", len(files), totalSize/1024/1024)
 	return nil
-}
+}