Nine surfaces declare a keyboard widget; zero implement one

[mpstaton]

Context:

• Build-Selector-And-Close-The-Keyboard-Contract.md

Nine surfaces across seven members declare role="menu", role="listbox" or role="radiogroup". None implements arrow-key navigation.

chat/ChatSurface                    arrowkeys=0
org-workbench/OrgSearch             arrowkeys=0
response-reviewer/ConnectorPalette  arrowkeys=0
sort-filter-lens/App                arrowkeys=0
search-and-add/ProviderPalette      arrowkeys=0
pack-runner/ConnectorPalette        arrowkeys=0
shell/DevelopersMenu                arrowkeys=0
shell/JumboPopdown                  arrowkeys=0
shell/WorkspaceSwitcher             arrowkeys=0

Two declare role="menu" with no menuitem children; one declares role="radiogroup" containing no radios — a widget a screen reader announces as structurally broken.

Each role is a promise: this is a widget you navigate with arrows, and Tab takes you out of it. All nine deliver a plain list of tab stops.

Selector--Listbox is built with 17 tests written before it (packages/shared-ui/test/selector.test.ts). Selector--Menu next. No --Radio: zero sightings.

Per-member adoption: failing test first, then refactor, then green.