[atable] fix for modal positioning

[crabinak]

@Alchez @agritheory related to the issue we were having with the amodal not positioning correctly. This fix changes the modal position to fixed while still auto-detecting edges (so it doesn't get cropped off-screen). The position of the modal uses the position of the cell instead of offset positioning, so it shouldn't matter what the parent is doing (I used some test wrapping divs as parents to ATable and gave them various positioning).

Let me know if this resolves that weird positioning issue that was occurring.

Example image: The modal right aligns with the page since it would otherwise overflow and get cropped.

[github-actions]

Coverage Report for ./atable

Status	Category	Percentage	Covered / Total
🔴	Lines	67.08% (🎯 70%)	161 / 240
🔴	Statements	68.11% (🎯 70%)	173 / 254
🟢	Functions	79.59% (🎯 70%)	39 / 49
🔴	Branches	46.23% (🎯 70%)	86 / 186

File Coverage

File	Stmts	Branches	Functions	Lines	Uncovered Lines
Changed Files
atable/src/components/ACell.vue	90.38%	62.5%	100%	90.19%	101, 124-127, 157, 165-167
atable/src/components/ATable.vue	55.55%	35.29%	81.81%	54.71%	107-111, 121-149, 163-164
atable/src/components/ATableModal.vue	46.66%	20%	50%	42.85%	22-45, 49
Unchanged Files
atable/src/utils.ts	100%	100%	100%	100%
atable/src/components/AExpansionRow.vue	0%	0%	0%	0%	33-3
atable/src/components/ARow.vue	64.28%	56.25%	75%	58.33%	51-65, 17
atable/src/components/ATableHeader.vue	100%	57.14%	100%	100%
atable/src/stores/table.ts	74%	50%	84.21%	73.91%	39-40, 53, 84-85, 107-111, 127, 134, 138-149, 176, 184-185, 191

Generated in workflow #547 for commit 906ab22 by the Vitest Coverage Report Action

[Alchez]

@crabinak I think the logic for rendering modals for the last few cells has maybe regressed. Here's what I see in the ATable default story

[crabinak]

@Alchez I added a line to include the Y position of the window scroll when calculating the maximum height. Let me know if this fixes it now.

[Alchez]

@crabinak This looks good. But I've added a commit based on some typing warnings in the IDE. Can you please check out the change locally and verify that the behaviour hasn't changed?

[crabinak]

@Alchez It is still working fine. Thanks!