test: fix the two suites failing on main

[datlechin]

macOS Tests has been red on every push to main since #3044, and iOS Tests went red once on #3052. Both are test defects, not app defects.

macOS: No menu names itself with accessibilityLabel

Failing on 9 consecutive main runs (35694031462 through 35812418402), always with one offender: TrailingPaneHeaderView.swift:107.

#3044 named the trailing pane's ellipsis menu with .accessibilityElement(children: .contain) followed by .accessibilityLabel. That is the only form that names a pull-down whose label draws only an icon: the label then names the container, not the menu. TrailingPaneSurfaceUITests.testTheInspectorMenuSwitchesTheRowToJSON asserts the name is "Inspector Options" and passes on CI (it read "" on the runner before #3044).

The static scanner in MenuDisclosureIndicatorTests predates that finding and flags any .accessibilityLabel in a menu's modifier chain. It now skips one that follows .accessibilityElement(children: .contain). A bare .accessibilityLabel on a menu is still flagged.

A new fixture test pins both sides, so the exemption cannot quietly widen:

• a menu with .accessibilityLabel alone is reported
• the same menu with .accessibilityElement(children: .contain) first is not

Negative control: with the exemption removed, the tree scan reports TrailingPaneHeaderView.swift:107 again and the fixture test fails.

iOS: A second question waits its turn instead of being refused

Failed on 35740949976 with queue.current?.id equal to the second prompt's id.

The test started both questions with async let. Each child task hops to the main actor on its own, so nothing orders the two ask calls, and the second question can be queued first. ConnectionPromptQueue is FIFO by call order and a real connect attempt asks its questions one after another, so the product is right and the test's ordering was a race. The test now waits for the first question to be on screen before asking the second.

Not changed

• BackgroundReleaseCoordinatorTests.inFlightReleaseSurvivesForegroundBounce hit its one-minute limit once (35604565186), while every test in that run reported about 108s of wall time on a cloned simulator. Since fix(datagrid): the filter bar, the pane menu's name, and the three red suites on main #3044 moved the suite to one simulator, the whole suite finishes in 0.29s.
• The filter bar, default sort and pane menu name failures on earlier runs were fixed by fix(datagrid): the filter bar, the pane menu's name, and the three red suites on main #3044. The JSON field UI failure on 35764975234 was fixed by test(datagrid): make the JSON field's regression tests able to fail #3059.

Testing

• Scanner tests run in a standalone harness built from the test file: all three pass on this tree, two fail with the exemption removed.
• ConnectionPromptQueueTests run 200 times on the iOS simulator: 200 repetitions (-test-iterations 200), 0 failures.
• swiftlint lint --strict on both files: 0 violations.