feat: add provider icons and system icons to menus, improve UI consistency

- Add provider asset icons (ChatGPT/Claude/Gemini) to menu items in ProjectsListView
- Add system icons (terminal, network) to menu submenus
- Fix sticky header interaction in ConversationTimelineView (move gesture handlers to inner content)
- Improve menu item consistency with assetImage parameter support

Author: loocor

views/ConversationTimelineView.swift

@@ -92,17 +92,17 @@ struct ConversationTimelineView: View {
                 isActive: isActive,
                 extraLineHeight: extraLineHeight
               )
+              .contentShape(Rectangle())
+              .onTapGesture {
+                withAnimation(.easeInOut(duration: 0.2)) {
+                  proxy.scrollTo(stickyTurnID, anchor: .top)
+                }
+              }
+              .hoverHand()
               Spacer(minLength: 0)
             }
             .padding(.leading, 12)
             .padding(.top, topPadding)
-            .contentShape(Rectangle())
-            .onTapGesture {
-              withAnimation(.easeInOut(duration: 0.2)) {
-                proxy.scrollTo(stickyTurnID, anchor: .top)
-              }
-            }
-            .hoverHand()
           }
         }
       }

views/ProjectsListView.swift

@@ -579,6 +579,22 @@ private struct ProjectTreeNodeView: View {
       }
     }
 
+    func providerAssetIcon(_ source: ProjectSessionSource) -> String {
+      switch source {
+      case .codex: return "ChatGPTIcon"
+      case .claude: return "ClaudeIcon"
+      case .gemini: return "GeminiIcon"
+      }
+    }
+
+    func assetIconForSessionSource(_ source: SessionSource) -> String {
+      switch source.baseKind {
+      case .codex: return "ChatGPTIcon"
+      case .claude: return "ClaudeIcon"
+      case .gemini: return "GeminiIcon"
+      }
+    }
+
     var menuItems: [SplitMenuItem] = []
     for base in requestedOrder where allowed.contains(base) {
       var providerItems = launchItems(for: base.sessionSource)
@@ -596,7 +612,7 @@ private struct ProjectTreeNodeView: View {
       menuItems.append(
         SplitMenuItem(
           id: "provider-\(base.rawValue)",
-          kind: .submenu(title: base.displayName, items: providerItems)
+          kind: .submenu(title: base.displayName, assetImage: providerAssetIcon(base), items: providerItems)
         ))
     }
 
@@ -607,6 +623,7 @@ private struct ProjectTreeNodeView: View {
           id: "fallback-\(sourceKey(fallbackSource))",
           kind: .submenu(
             title: fallbackSource.branding.displayName,
+            assetImage: assetIconForSessionSource(fallbackSource),
             items: launchItems(for: fallbackSource)
           )))
     }