[BUG] Unexpected ExpandE and GetV fusion

[BingqingLyu]

Describe the bug

Currently in the new compilation stack, we will fused EdgeExpand and GetVertex when the edges output by EdgeExpand is not necessary. However, this may occur a bug in the following query on LDBC:

MATCH (friend:PERSON)<-[:HASCREATOR]-(comment:COMMENT)
Return count(friend)

In this case, EdgeExpand(type=HASCREATOR, OPT=EDGE) and GetV(type=COMMENT, OPT=SRCV) are fused into EdgeExpand(type=HASCREATOR, OPT=VERTEX), while the fused edge expansion actually expands HASCREATOR-COMMENT and HASCREATOR-POST, and it is not as expected.

This should fixed by defining edge type as a triplet (instead of a single type_id).

[github-actions]

/cc @BingqingLyu, this issus/pr has had no activity for for a long time, could you folks help to review the status ?
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