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/address_transfer_dialog.h

@@ -93,7 +93,7 @@ public:
             // Arrow
             {
                 float arrowCX = ImGui::GetContentRegionAvail().x * 0.5f;
-                ImGui::SetCursorPosX(arrowCX - 8.0f);
+                ImGui::SetCursorPosX(arrowCX - 8.0f * dp);
                 ImFont* iconFont = Type().iconMed();
                 float fsz = ScaledFontSize(iconFont);
                 ImVec2 pos = ImGui::GetCursorScreenPos();
@@ -312,7 +312,8 @@ private:
 
         ImGui::Spacing();
         ImGui::Spacing();
-        float btnW = 120.0f;
+        const float dp = Layout::dpiScale();
+        float btnW = 120.0f * dp;
         ImGui::SetCursorPosX((ImGui::GetContentRegionAvail().x - btnW) * 0.5f);
         if (TactileButton(TR("close"), ImVec2(btnW, 0))) {
             s_open = false;