Drop redundant safecsv WriteRow helper

WriteRow was a variadic alias for Write(SanitizeRecord(...))
with no extra safety or column checks. Export call sites already
use []string headers; matching encoding/csv keeps one API surface.

Signed-off-by: Cursor Agent <cursoragent@cursor.com>

Co-authored-by: Bryan FRIMIN <bryan@frimin.fr>

pkg/safecsv/cell_test.go

@@ -50,7 +50,7 @@ func TestWriterWrite(t *testing.T) {
 	var buf bytes.Buffer
 
 	w := NewWriter(&buf)
-	require.NoError(t, w.WriteRow("ok", "=evil"))
+	require.NoError(t, w.Write([]string{"ok", "=evil"}))
 	w.Flush()
 	require.NoError(t, w.Error())