worker: ocr upload as utf8

backend/src/workers/ocr.rs

@@ -172,7 +172,7 @@ impl JobHandler for GenerateOcrTextJob {
             .put_object(
                 &s3_key,
                 generation.text.into_bytes(),
-                Some("text/plain".into()),
+                Some("text/plain; charset=utf-8".into()),
                 None,
             )
             .await