Composition child edit dialog reloads from DB on open, showing a stale value that disagrees with the grid

[mig-sam]

Environment

Jmix version: 3.0
Jmix Studio Plugin Version: 3.1.SNAPSHOT8083-262
IntelliJ version: IntelliJ IDEA 2026.2.1 RC

Bug Description

When a @Composition child is modified in memory but not yet saved (e.g. by an ItemPropertyChangeEvent listener that resets a sibling), reopening that child in its edit dialog shows the stale database value, not the current in-memory value. The parent grid (bound to the in-memory collection container) and the child edit dialog therefore disagree. It specifically affects listener-modified siblings, not the line you edit directly: a child you edit yourself reopens with its in-memory (unsaved) value, whereas a sibling changed only by the listener reopens with the stale DB value. So the reload does not honor the parent context's dirty state for the listener-injected edit.

Steps To Reproduce

1.Launch demo project
2.Check that Order6DetailView.java has next listner:

    public void onLines6DcItemPropertyChange(final InstanceContainer.ItemPropertyChangeEvent<Line6> event) {
        if ("primary".equals(event.getProperty()) && Boolean.TRUE.equals(event.getValue())) {
            Line6 changed = event.getItem();
            for (Line6 line : lines6Dc.getItems()) {
                if (line != changed && Boolean.TRUE.equals(line.getPrimary())) {
                    line.setPrimary(false);
                }
            }
        }
    }

3.Navigate to Order6s view. Open ORD-1 for edit. Baseline: Line A = primary (true), Line B/C = false
4.Open Line B in the dialog → check Primary → OK. The listener resets Line A to false.
5.The grid now shows Line A = False (correct in-memory value)
6.Open Line A in the edit dialog

Current Behavior

The Primary checkbox is checked (true) — the stale DB value.

Expected Behavior

The Primary checkbox is unchecked (false), matching the grid

Sample Project

DataContext31sn_0901.zip