cold_clone: handle SQLite BLOB-as-str affinity in just-enough strip

Some rows in shards-genesis-v2 came back from the chunks.content BLOB
column as  instead of bytes — SQLite's type-affinity rule lets a
BLOB-affinity column hold any storage class. The strip-and-upload path
crashed on bytes(some_str) without an encoding. latin-1 preserves
arbitrary byte values 1:1, so the leaf_hash check still matches.

arborist/cold_clone.py

@@ -185,8 +185,19 @@ def _strip_chunk_content_and_dump_blobs(
                 f"WHERE chunk_id IN ({placeholders})",
                 batch_ids,
             ).fetchall()
+            # SQLite type affinity: a `BLOB` column can come back as
+            # bytes / bytearray / memoryview, OR as `str` if the value
+            # was originally INSERTed as text. latin-1 preserves
+            # arbitrary byte values 1:1 (codepoints 0..255) so the
+            # hash check below still matches.
+            def _as_bytes(v):
+                if isinstance(v, (bytes, bytearray)):
+                    return bytes(v)
+                if isinstance(v, memoryview):
+                    return v.tobytes()
+                return v.encode("latin-1")
             triples = [
-                (cid, lh, bytes(c)) for cid, lh, c in rows if c is not None
+                (cid, lh, _as_bytes(c)) for cid, lh, c in rows if c is not None
             ]
             with ThreadPoolExecutor(max_workers=upload_workers) as ex:
                 for cid in ex.map(_upload, triples):