Accepting an enum value (e.g. "on-track") re-ran the chained refresh,
which re-matched the value and reopened the popup. Chain only after
completing a key, when there are still values to offer.
Anchor a suggestion list at the caret (monospace metrics, re-anchored on
scroll), with arrow/Enter/Tab/Esc handling and click-to-accept. Accepting
a key like `status` chains straight into its value suggestions.
