feat(chat): "Request" pill on unsolicited conversations in the list

The conversation list now marks a pending stranger request with a small
"Request" pill (bottom-right of the row), so it's distinguishable before you
open it; the preview text is clipped to the pill's left so they don't overlap.
Completes the request-affordance pair with the in-thread Accept/Block card.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/ui/windows/chat_tab.cpp

@@ -1022,9 +1022,21 @@ void RenderChatTab(App* app)
             dl->AddText(nameFont, nameSz, ImVec2(textX, p.y + pad),
                         c.hidden ? material::OnSurfaceMedium() : material::OnSurface(), c.peerName.c_str());
             dl->PopClipRect();
+            // Pending-request pill (bottom-right) for an unsolicited stranger; the preview is clipped to its left.
+            float previewRight = mx.x - pad;
+            if (c.pendingRequest) {
+                const char* rl = TR("chat_request_pill");
+                const ImVec2 rs = metaFont->CalcTextSizeA(metaSz, FLT_MAX, 0.0f, rl);
+                const float px = 6.0f * dp, py = 1.0f * dp;
+                const ImVec2 pmax(mx.x - pad, p.y + rowH - pad + py);
+                const ImVec2 pmin(pmax.x - rs.x - 2.0f * px, pmax.y - rs.y - 2.0f * py);
+                dl->AddRectFilled(pmin, pmax, material::WithAlpha(material::Warning(), 60), (rs.y + 2.0f * py) * 0.5f);
+                dl->AddText(metaFont, metaSz, ImVec2(pmin.x + px, pmin.y + py), material::Warning(), rl);
+                previewRight = pmin.x - pad;
+            }
             // Preview (bottom, clipped to the text column, muted).
             const std::string preview = previewOf(c.lastBody);
-            dl->PushClipRect(ImVec2(textX, p.y), ImVec2(mx.x - pad, mx.y), true);
+            dl->PushClipRect(ImVec2(textX, p.y), ImVec2(std::max(textX, previewRight), mx.y), true);
             dl->AddText(metaFont, metaSz, ImVec2(textX, p.y + rowH - pad - metaSz),
                         material::OnSurfaceMedium(), preview.c_str());
             dl->PopClipRect();

src/util/i18n.cpp

@@ -232,6 +232,7 @@ void I18n::loadBuiltinEnglish()
         strings_["chat_empty_hint"] = "No conversations yet. Messages you receive will appear here.";
         strings_["chat_you"] = "You";
         strings_["chat_contact_request"] = "contact request";
+        strings_["chat_request_pill"] = "Request";
         strings_["chat_request_title"] = "New contact request";
         strings_["chat_request_body"] = "This person isn't in your contacts. Accept to add them, or block to delete this conversation and ignore them.";
         strings_["chat_request_accept"] = "Accept";