feat(ui): in-app FAQ, DPI-scaling audit fixes, mining/stratum polish + localize strings

Bundles the session's UI work (the touched files carry several of these
changes together, so they are committed as one coherent UI batch):

- FAQ: new RenderFaqDialog + data-driven faq_content, opened from a
  status-bar "?" (and the Windows title bar), styled like the Wallets
  modal with search, Wallet/Daemon tabs, and smooth scroll.
- DPI/font-scale audit: multiply hand-drawn absolute geometry by
  Layout::dpiScale() across ~30 files so nothing renders native-size at
  HiDPI / font_scale 1.5 (verified with a full sweep at 1.5x).
- Mining: chart now fills the horizontal space; thread stepper +/- buttons
  match the input-box height; move the stratum-host toggle into
  Node & Security (v1.3.0+).
- Settings: fix the auto-shield status text overlapping the grid.
- Sidebar: drop the peer-count badge on the Network button.
- i18n: wrap 193 hardcoded literals with TR() (keys/translations added in
  the preceding i18n commit), so the security/PIN/lock flow, seed-backup
  wizard, and witness-rebuild dialog localize.

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

src/ui/windows/bootstrap_download_dialog.h

@@ -144,7 +144,7 @@ private:
 
         if (!s_bootstrap) {
             s_state = State::Failed;
-            s_errorMsg = "Bootstrap not initialized";
+            s_errorMsg = TR("grpc_bootstrap_not_initialized");
             return;
         }
 
@@ -227,7 +227,7 @@ private:
                 s_state = State::Done;
             } else {
                 s_errorMsg = finalProg.error;
-                if (s_errorMsg.empty()) s_errorMsg = "Bootstrap failed";
+                if (s_errorMsg.empty()) s_errorMsg = TR("grpc_bootstrap_failed");
                 s_state = State::Failed;
             }
             s_bootstrap.reset();