feat(settings): rename RPC toggle to "RPC Connection..." (Tools & Actions style)

Rename the RPC collapsible header from "RPC CONNECTION" to "RPC Connection..." and
render it in the body2 font so it matches the "Tools & Actions..." toggle exactly.

Full-node build clean; hygiene clean.

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

src/ui/pages/settings_page.cpp

@@ -2117,7 +2117,7 @@ void RenderSettingsPage(App* app) {
                 // -------------------- RPC (collapsible, like Tools & Actions) --------------------
                 ImGui::Dummy(ImVec2(0, Layout::spacingSm()));
                 {
-                    ImFont* rpcHdrFont = Type().overline();
+                    ImFont* rpcHdrFont = body2;  // match the "Tools & Actions..." toggle style
                     const char* rpcArrow = s_settingsState.rpc_expanded ? ICON_MD_EXPAND_LESS : ICON_MD_EXPAND_MORE;
                     ImGui::PushFont(body2);
                     ImGui::PushStyleColor(ImGuiCol_Button, ImVec4(0,0,0,0));