ComboboxInputTrigger puts the combobox states on a role-less div #551

• Where: combobox_input_trigger.rb: aria-expanded and aria-haspopup="listbox" on the wrapper div; the <input> has no role="combobox", aria-controls or aria-activedescendant. Snapshot combobox/input_trigger.
• Effect: ARIA 1.2 puts those states on the element with the combobox role; on a role-less div they are not conveyed, and the listbox relationship is never announced.
• Fix: move role: "combobox", aria-haspopup, aria-expanded and aria-controls onto the input; re-record combobox/*.

Surfaced by the strict lane of the golden HTML suite (PR #548), which pins what 1.6 renders today — this defect included. Per maintainer decision (2026-09-19) main stays as is: this is addressed on the 2.0 line, and the golden snapshots that pin it are re-recorded there with the diff reviewed.

Source: design/v2/follow-up-issues.md.