url-option for upload checksum type

url-param / header `ck` specifies hashing algo;
md5 sha1 sha256 sha512 b2 blake2 b2s blake2s

value 'no' or blank disables checksumming,
for when copyparty is running on ancient gear
and you don't really care about file integrity

copyparty/util.py

@@ -2796,6 +2796,26 @@ def yieldfile(fn: str, bufsz: int) -> Generator[bytes, None, None]:
             yield buf
 
 
+def justcopy(
+    fin: Generator[bytes, None, None],
+    fout: Union[typing.BinaryIO, typing.IO[Any]],
+    hashobj: Optional["hashlib._Hash"],
+    max_sz: int,
+    slp: float,
+) -> tuple[int, str, str]:
+    tlen = 0
+    for buf in fin:
+        tlen += len(buf)
+        if max_sz and tlen > max_sz:
+            continue
+
+        fout.write(buf)
+        if slp:
+            time.sleep(slp)
+
+    return tlen, "checksum-disabled", "checksum-disabled"
+
+
 def hashcopy(
     fin: Generator[bytes, None, None],
     fout: Union[typing.BinaryIO, typing.IO[Any]],
@@ -3506,7 +3526,6 @@ def runhook(
     txt: str,
 ) -> dict[str, Any]:
     assert broker or up2k  # !rm
-    asrv = (broker or up2k).asrv
     args = (broker or up2k).args
     vp = vp.replace("\\", "/")
     ret = {"rc": 0}