Bug of IGLatticeMesh

[Juddd]

Describe the bug
The vertices are outside the region in IGLatticeMesh

To Reproduce

Needs["IGraphM`"]
len = 6;
Show[Graphics[SSSTriangle[len, len, len]], 
 IGMeshGraph@IGLatticeMesh["Triangular", SSSTriangle[len, len, len]]]

Version information

The output of IGraphM`Developer`GetInfo[] is:

Mathematica version: 
13.3.1 for Microsoft Windows (64-bit) (July 24, 2023); Release \
number: 1

Package version: 
0.6.5 (December 21, 2022)

Package location: 
C:\Users\zyd19\AppData\Roaming\Mathematica\Paclets\Repository\IGraphM-\
0.6.5\Kernel\init.m

Library location: 
C:\Users\zyd19\AppData\Roaming\Mathematica\Paclets\Repository\IGraphM-\
0.6.5\LibraryResources\Windows-x86-64\IGraphM.dll

IGVersion[]: 
IGraph/M 0.6.5 (December 21, 2022)
igraph 0.9.10-23-g5635203bd (Dec 21 2022)
Microsoft Windows (64-bit)

Build settings: 
None

Operating system: 
Microsoft Windows [°æ\[PlusMinus]¾ 10.0.22631.2715]