fix(a11y): names that carry what they show; the unused-key check stops covering whole files

- The palette launcher's name replaced its visible "Jump to…" (and the key cap's its "Ctrl K"):
  a voice-control "click Jump to" matched nothing (WCAG 2.5.3). Each name contains its text now.
- SegmentedToggle's `title` was only a tooltip on a non-focusable box — the live search's "how
  many per batch" hint reached no keyboard or screen-reader user. It is the group's accessible
  description, standalone and captioned alike.
- The unused-key contract let a template like `card.${status}` cover its whole namespace, which hid
  five dead keys (deleted). Dynamic keys are matched by shape (`editor.*.hint`); a bare namespace
  shape covers nothing, and the audit/quota namespaces are now held both ways by backendIds.
- CLAUDE.md's "FE control" row matches the lint rule it cites; each no-restricted-syntax entry has
  its reason directly above it.

CLAUDE.md

@@ -92,7 +92,7 @@ CQRS, a repository/DI framework, a router library, a generic CRUD-router factory
 | FE keyboard shortcut    | a row in `lib/keymap.ts` + `dispatch()`                      | a private `keydown` listener with its own key literals |
 | FE list/grid keys       | `NavGrid`/`keyboardNav` + `navItemAttrs` + `data-nav-open`   | a private arrow-key / roving-tabindex handler          |
 | FE view push (history)  | `rememberNavPosition()` right before `history.pushState`     | a push that forgets: Back strands focus on `<body>`    |
-| FE control              | the chip/segmented primitives (`Select` only for >6 options) | a native `<select>`                                    |
+| FE control              | `SegmentedToggle`; a long or user's list: `FilterSelect`     | a native `<select>` (lint-enforced)                    |
 | FE loading/empty/error  | `QueryState` / `StateMessage`                                | ad-hoc conditionals                                    |
 | FE failed write         | `meta.failTitle`, else `notifyActionError(err, title)`       | a bare `catch {}` or `notify()` with no error attached |
 | FE network call         | `req`/`uploadReq`/`beacon`, or `lib/http.ts` `send` (public pages) | a bare `fetch`/`XMLHttpRequest`/`WebSocket` (lint-enforced) |