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-workspace/src/client/WorkspaceBrowser.tsx

@@ -21,7 +21,10 @@ import { ProjectRowItem, SessionNodeItem } from './rows/Rows.tsx'
 import { WorkspaceCreateFlow } from './WorkspacePicker.tsx'
 import css from './WorkspaceBrowser.module.css'
 
-/** Column slide length (--ds-transition-duration-slow): rail-search focus waits it out — focus() forces a synchronous layout and would jank the slide. */
+/**
+ * Column slide length (--ds-transition-duration-slow): rail-search focus waits it out —
+ * focus() forces a synchronous layout and would jank the slide.
+ */
 const EXPAND_SLIDE_MS = 300
 
 const GROUP_BY_ITEMS = [
@@ -292,7 +295,7 @@ export function WorkspaceBrowser({
     setRenameError(null)
   }
   const confirmRename = () => {
-    if (renameBlocked || renameTarget === null) return
+    if (renameBlocked) return
     setRenaming(true)
     setRenameError(null)
     renameWorkspace(renameTarget.workspaceId, renameTrimmed).then(() => {
@@ -481,7 +484,7 @@ export function WorkspaceBrowser({
             <Button variant="outline" disabled={deleting} onClick={closeDelete}>Cancel</Button>
             <Button
               variant="outline"
-              className={css.deleteAction!}
+              className={css.deleteAction}
               disabled={deleting}
               onClick={confirmDelete}
             >

packages/client/ui-workspace/src/client/WorkspacePicker.tsx

@@ -161,8 +161,8 @@ export function WorkspaceCreateFlow({
         title={folderConflict ? 'A workspace with this name already exists' : 'Couldn’t open folder'}
         footer={(
           <>
-            <Button variant="outline" className={css.modalAction!} onClick={closeModal}>Cancel</Button>
-            <Button variant="primary" className={css.modalAction!} onClick={openLocalFolder}>Choose again</Button>
+            <Button variant="outline" className={css.modalAction} onClick={closeModal}>Cancel</Button>
+            <Button variant="primary" className={css.modalAction} onClick={openLocalFolder}>Choose again</Button>
           </>
         )}
       >
@@ -179,10 +179,10 @@ export function WorkspaceCreateFlow({
         description="The name is used for both the workspace and its new folder."
         footer={(
           <>
-            <Button variant="outline" className={css.modalAction!} disabled={creating} onClick={closeModal}>Cancel</Button>
+            <Button variant="outline" className={css.modalAction} disabled={creating} onClick={closeModal}>Cancel</Button>
             <Button
               variant="primary"
-              className={css.modalAction!}
+              className={css.modalAction}
               disabled={creating || normalizedWorkspaceName === '' || duplicateWorkspaceName}
               onClick={confirmCreate}
             >