fix(ui): relocate + reword node auto-shield status; add chat-management FAQ entry

- Auto-shield status: the node's z_autoshieldstatus disabled_reason was echoed
  verbatim ("HD seed origin is not known-recoverable; back the seed up and pass
  -autoshield=1") and drawn INSIDE the Wallet OPTIONS checkbox grid, wedging a
  full-width line between the checkboxes. Move it to a full-width note BELOW the
  grid, and replace the raw daemon text with friendly, actionable wording keyed
  on the seed_recoverable flag (back up your seed to enable it); the raw daemon
  reason is kept on hover. Adds App::daemonAutoShieldSeedRecoverable().
- FAQ: add a Chat & Contacts entry ("How do I hide, delete, or block a
  conversation?") covering the hide / delete-revive / delete-&-block actions and
  the local-only caveat — data + i18n only, no UI code change.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/ui/windows/faq_content.cpp

@@ -50,6 +50,7 @@ const std::vector<FaqSubcategory>& walletFaq()
             { "faq_w_chat_1_q", "faq_w_chat_1_a" },
             { "faq_w_chat_2_q", "faq_w_chat_2_a" },
             { "faq_w_chat_3_q", "faq_w_chat_3_a" },
+            { "faq_w_chat_4_q", "faq_w_chat_4_a" },
         }},
         { "faq_w_set_title", {
             { "faq_w_set_1_q", "faq_w_set_1_a" },