fix(qa): resolve QA-pass issues #122–#134

Batch of fixes from the automated QA pass on develop. Each was reproduced and
then verified fixed live (browser/curl); logic-bearing fixes have unit tests.

Functional bugs:
- #122 collab-token was capped by the anonymous public-share-AI throttler (5/min);
  skip all non-AUTH named throttlers on this auth-guarded, client-cached route.
- #123 editor onAuthenticationFailed threw `jwtDecode(undefined)` and never
  reconnected; read the token via a ref, guard the decode (incl. missing exp),
  and refetch+reconnect on any auth failure.
- #124 a slash command containing a space ("/Heading 1") inserted literal text;
  enable allowSpaces and close the menu when the query matches no items.
- #125 space slug auto-gen produced uppercase initials for multi-word names;
  computeSpaceSlug now yields a lowercase alphanumeric slug.
- #126 AI chat window position/size now persisted (atomWithStorage) across reload;
  also fixes a latent ResizeObserver-attach bug on first open.
- #127 workspace name update accepted URLs; add @NoUrls (parity with setup).
- #132 icon-columns 4/5 passed calc() into SVG width/height attrs (console spam);
  size via style. share-for-page query returns null instead of undefined.
- #134 "Reindex now" counter looked stuck: reindex runs async; the client now
  polls coverage (bounded) so the counter climbs live; misleading server comment
  reworded.

UX / consistency:
- #128 add success toasts to favorite/label/avatar/member-(de)activate.
- #129 "1 result found" pluralization; hide the single-option Type filter.
- #130 replace raw Zod strings with friendly messages (name/password/group).
- #131 unify "Untitled" casing in tree/breadcrumb/tab; stop force-uppercasing
  space-name chips; fix confirm-dialog labels (Cancel / Remove), invite
  placeholder typo, Export/Move-to-space labels.
- #133 disable profile Save when clean; toast on unsupported avatar image;
  style the invalid-invitation page with a CTA; hide Share for read-only users;
  align the dictation "not configured" message; "Go to login page" typo.

Tests: computeSpaceSlug, workspace-name NoUrls DTO, share-query null
normalization, slash getSuggestionItems empty-close.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

apps/client/src/features/page/tree/components/space-tree-node-menu.tsx

@@ -148,7 +148,7 @@ export function NodeMenu({ node, canEdit }: NodeMenuProps) {
             variant="subtle"
             color="gray"
             className={classes.actionIcon}
-            aria-label={t("Page menu for {{name}}", { name: node.name || t("untitled") })}
+            aria-label={t("Page menu for {{name}}", { name: node.name || t("Untitled") })}
             tabIndex={-1}
             onClick={(e) => {
               e.preventDefault();
@@ -199,7 +199,7 @@ export function NodeMenu({ node, canEdit }: NodeMenuProps) {
               openExportModal();
             }}
           >
-            {t("Export page")}
+            {t("Export")}
           </Menu.Item>
 
           {canEdit && (
@@ -223,7 +223,7 @@ export function NodeMenu({ node, canEdit }: NodeMenuProps) {
                   openMovePageModal();
                 }}
               >
-                {t("Move")}
+                {t("Move to space")}
               </Menu.Item>
 
               <Menu.Item