chore(lint): clear the semantic .tsx backlog

Hand fixes for the findings --fix cannot touch, mirroring the fixes
already applied on the fe-docs feature branch (same file, same shape)
so its eventual rebase resolves cleanly:

- restore the return the no-confusing-void-expression autofix ate in
  useAbsentSnapshot (typed S | undefined; hook call kept for hook-order
  stability, undefined returned explicitly);
- re-type DOM queries the no-unnecessary-type-assertion autofix broke:
  getByRole<HTMLButtonElement>(...) generics instead of the removed
  as-casts (the eslint program and the client tsconfig aggregate
  disagree about these casts; the generic form satisfies both);
- justified eslint-disable for the deliberate legacy paths: keyCode 229
  IME-composition detection, execCommand clipboard fallbacks, lib.dom
  clipboard optionality, and the any-typed Reflect.get/this probes in
  test fakes;
- drop the dead react/no-danger directive (eslint-plugin-react is not
  loaded, so the rule never applied) keeping its shiki rationale;
- delete the tautological 'Z' comparison and the renameTarget null
  check already implied by renameBlocked;
- css-module non-null assertions replaced by type widening
  (Button className, TAG_CLASS Record) per the established pattern;
- misc: max-len comment wraps, void generic drop in the deferred test
  helper, unused type imports, floating selectWorkspace promises voided,
  member-delimiter newlines in inline type literals.

packages/client/ui-question/src/client/QuestionComposer.tsx

@@ -37,6 +37,8 @@ export function parseQuestionTitle(title: string): string {
 
 /** Return whether a textarea key event belongs to an active IME composition. */
 function isComposing(event: KeyboardEvent<HTMLTextAreaElement>): boolean {
+  // keyCode 229 is the legacy IME-composition signal engines emit without isComposing.
+  // eslint-disable-next-line @typescript-eslint/no-deprecated
   return event.nativeEvent.isComposing || event.nativeEvent.keyCode === 229
 }
 
@@ -61,7 +63,10 @@ function QuestionFlow({ pending }: { pending: PendingQuestion }) {
   })))
   const [busy, setBusy] = useState<'answer' | 'cancel' | null>(null)
   const [error, setError] = useState<string | null>(null)
+  // index stays in bounds (every setIndex site clamps) and drafts mirrors questions 1:1.
+  // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
   const question = questions[index]!
+  // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
   const draft = drafts[index]!
   const hasOptions = (question.options?.length ?? 0) > 0