Margin cache misses data

[hombit]

Bug report

I found that some data is missed in PS1 OTMO margin catalog generated by @camposandro on PSC. For example, margin file Norder=5/Dir=0/Npix=1000.parquet misses some points near the corners of the partition.

Here is few data points from the catalog in three categories: correct margin points, missed points from a neighbor partition, non-margin points from a neighbor partition.

_healpix_29,raMean,decMean,kind
281944101599211816,11.25802281,78.28414956,correct_hats_margin
281944101616853037,11.257565935411892,78.28447927669177,correct_hats_margin
281944101708050912,11.25438323,78.28465534,correct_hats_margin
281944101814299999,11.25798339,78.28502523999998,correct_hats_margin
281944101965822867,11.25629879,78.28579152999998,correct_hats_margin
281944101081037263,11.26724867,78.28314478,missed_hats_margin
281944101431231287,11.26660872,78.28447674999998,missed_hats_margin
281944102169687059,11.26730961,78.28523860999998,non-margin
281944102340144316,11.26968296,78.28613398,non-margin
281944102520090038,11.26865726,78.28766018,non-margin

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