fix(ui): make HiDPI-overflowing containers scrollable — wizard, overlay dialogs, balance recent-tx

At font_scale 1.5 (dpiScale 1.5) three fixed, non-scrolling containers clipped
content off the bottom with no scroll escape:

- First-run wizard: the hand-drawn cards grow ~1.5x past the fixed window,
  pushing Continue / Encrypt & Continue / Skip off-screen (a setup blocker).
  Inject a wheel-driven scroll offset into the layout seed + a scroll indicator;
  gate the wheel on !IsPopupOpen + NoPopupHierarchy so an open combo popup does
  not scroll the wizard behind it. No-op at 1.0x.
- Overlay dialogs (BeginOverlayDialog): auto-height cards taller than the
  viewport (About, Request Payment) ran their footer off the bottom. Add a
  sticky per-open overflow flag that clamps the card to the viewport and makes
  the content child scrollable; short dialogs still center unchanged. Give the
  nested settings clear-history confirm its own idSuffix so it can't inherit the
  parent dialog's overflow state or collide on the child window id.
- Balance Recent Transactions: the dp-scaled address card evicted the recent-tx
  list off the non-scrolling tab host. Cap the card inside RenderSharedAddressList
  against the space that actually remains (minus a caller-provided reserve) so
  the section below stays on-screen — covers all 10 balance layouts.

Verified at font_scale 1.5 across full-node + Lite + Windows (ctest green) and an
adversarial diff review (two low-severity regressions found + fixed).

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

src/ui/windows/settings_window.cpp

@@ -478,7 +478,12 @@ void RenderSettingsWindow(App* app, bool* p_open)
             
             // Confirmation dialog
             if (s_confirm_clear_ztx) {
-                if (material::BeginOverlayDialog(TR("confirm_clear_ztx_title"), &s_confirm_clear_ztx, 480.0f, 0.94f)) {
+                // Distinct idSuffix: this confirm renders nested inside (and the same frame as) the parent
+                // settings dialog, so it must not share the default ##OverlayDialogContent key — otherwise it
+                // inherits the parent's OverlayCardState (incl. the sticky overflow flag) and collides on the
+                // child window id.
+                if (material::BeginOverlayDialog(TR("confirm_clear_ztx_title"), &s_confirm_clear_ztx, 480.0f,
+                                                 0.94f, 0.85f, "settings_clearztx")) {
                     material::DialogWarningHeader(TR("warning"), ImVec4(1.0f, 0.6f, 0.0f, 1.0f));
 
                     ImGui::Spacing();