Update duckdb index files

.gitattributes

@@ -71,3 +71,4 @@ default/dac_16k/index.duckdb filter=lfs diff=lfs merge=lfs -text
 default/encodec_24k_24bps/index.duckdb filter=lfs diff=lfs merge=lfs -text
 default/funcodec_zh_en_16k_nq32ds320/index.duckdb filter=lfs diff=lfs merge=lfs -text
 default/speech_tokenizer_16k/index.duckdb filter=lfs diff=lfs merge=lfs -text
+default/funcodec_zh_en_16k_nq32ds640/index.duckdb filter=lfs diff=lfs merge=lfs -text

default/funcodec_zh_en_16k_nq32ds640/index.duckdb

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:903780e551541ac9fbb5c421ec3effeed840b3049050169a0b9a24afa2dbfc73
+size 2109440