feat: profile avatar upload + share_conv_keys rpc + favicon + smtp tweaks

design_handoff_chatapp/styles/rail.css

@@ -0,0 +1,53 @@
+/* Rail layout — Discord-style icon sidebar */
+.rail-layout {
+  flex: 1;
+  display: grid;
+  grid-template-columns: 64px 280px 1fr;
+  overflow: hidden;
+  min-height: 0;
+}
+.icon-rail {
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  padding: 12px 0;
+  gap: 6px;
+}
+.rail-brand {
+  width: 44px; height: 44px;
+  border-radius: 14px;
+  display: flex; align-items: center; justify-content: center;
+  background: var(--accent, #4F46E5);
+  color: #fff;
+  margin-bottom: 4px;
+}
+.rail-divider { width: 32px; height: 2px; background: rgba(128,128,128,0.2); border-radius: 1px; margin: 4px 0; }
+.rail-btn {
+  width: 44px; height: 44px;
+  border-radius: 14px;
+  display: flex; align-items: center; justify-content: center;
+  color: var(--fg-muted);
+  position: relative;
+  transition: all 0.15s;
+}
+.rail-btn:hover { background: rgba(128,128,128,0.1); color: var(--fg); border-radius: 12px; }
+.rail-btn.active { background: var(--accent); color: #fff; border-radius: 12px; }
+.rail-pill {
+  position: absolute;
+  left: -12px; top: 50%; transform: translateY(-50%);
+  width: 4px; height: 24px;
+  background: var(--fg);
+  border-radius: 0 3px 3px 0;
+}
+.rail-chatlist { display: flex; flex-direction: column; }
+.rail-chatlist .chat-items { flex: 1; }
+.rail-user {
+  padding: 10px 12px;
+  display: flex; align-items: center; gap: 10px;
+  flex-shrink: 0;
+}
+
+.variant-clean.layout-rail .icon-rail { background: var(--bg-2); border-right: 1px solid var(--line); }
+.variant-clean.layout-rail .rail-chatlist { background: var(--bg-3); border-right: 1px solid var(--line); }
+.variant-clean.layout-rail .rail-user { background: var(--bg-2); border-top: 1px solid var(--line); }
+.variant-clean.layout-rail .rail-brand { background: var(--accent); color: #fff; }