fix(agentcompat): validate evidence modes by platform

Co-authored-by: naiba/CloudCode <hi+cloudcode@nai.ba>

integration/agentcompat/internal/evidence/directory_permissions_other.go

@@ -0,0 +1,23 @@
+//go:build !aix && !darwin && !dragonfly && !freebsd && !linux && !netbsd && !openbsd && !solaris && !windows
+
+package evidence
+
+import (
+	"errors"
+	"fmt"
+	"os"
+)
+
+func validateEvidenceDirectoryMode(info os.FileInfo) error {
+	if info.Mode().Perm() != 0o700 {
+		return errors.New("evidence directory must use mode 0700")
+	}
+	return nil
+}
+
+func validateEvidenceFileMode(info os.FileInfo, relative string) error {
+	if info.Mode().Perm() != 0o600 {
+		return fmt.Errorf("evidence file must use mode 0600: %s", relative)
+	}
+	return nil
+}