Improve tab bar color contrast in light and dark modes (#55)

* feat: improve tab bar color contrast in light and dark modes

Update tab bar unselected item color from 40% to 60% opacity for better
contrast and visibility in both light and dark modes.

Changes:
- Light mode: selected uses dark color, unselected uses 60% opacity dark (was 40%)
- Dark mode: selected uses white, unselected uses 60% opacity white (was 40%)

The subtle difference (100% vs 60%) provides better visual feedback while
maintaining a clean, modern look consistent with iOS design patterns.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

* fix: improve tab bar color configuration using SwiftUI modifiers

Fix tab bar colors by using proper SwiftUI approach instead of UIKit appearance APIs:
- Use .tint(Color.primary) for selected items (auto-adapts to light/dark mode)
- Set appearance.stackedLayoutAppearance for unselected text colors
- Remove UITabBar.appearance().tintColor to fix dark mode color reversal

Light mode: selected=black, unselected=light gray (78%)
Dark mode: selected=white, unselected=dim gray (60%)

Text colors now work correctly, icon colors need further fix.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

* fix: simplify tab bar color configuration with accentColor

Simplify the tab bar color implementation:
- Use UITabBar.appearance().unselectedItemTintColor for unselected items (both icons and text)
- Use .accentColor(Color.primary) modifier on TabView for selected items
- Remove complex UITabBarAppearance layout configurations

This simpler approach should properly apply colors to both icons and text:
- Light mode: selected=black, unselected=light gray (78%)
- Dark mode: selected=white, unselected=dim gray (60%)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

---------

Co-authored-by: Claude <noreply@anthropic.com>

Author: graycreate

V2er/View/MainPage.swift

@@ -24,6 +24,23 @@ struct MainPage: StateView {
         store.appState.feedState.feedInfo.unReadNums
     }
 
+    init() {
+        // Configure unselected item color using UITabBar.appearance()
+        // Selected color is controlled by .accentColor() modifier on TabView
+        let unselectedColor = UIColor { traitCollection in
+            switch traitCollection.userInterfaceStyle {
+            case .dark:
+                // Dark mode: dim gray (60% white)
+                return UIColor(red: 0.6, green: 0.6, blue: 0.6, alpha: 1.0)
+            default:
+                // Light mode: very light gray (78% gray - very subtle)
+                return UIColor(red: 0.78, green: 0.78, blue: 0.78, alpha: 1.0)
+            }
+        }
+
+        UITabBar.appearance().unselectedItemTintColor = unselectedColor
+    }
+
     // Create an intermediate binding that captures all tab selections
     // This is the proper SwiftUI way to detect same-tab taps without UIKit
     private var tabSelection: Binding<TabId> {
@@ -85,6 +102,7 @@ struct MainPage: StateView {
                     }
                     .tag(TabId.me)
                 }
+                .accentColor(Color.primary)  // This controls the selected icon color in TabView
 
                 // Filter menu overlay - only render when needed
                 if state.selectedTab == .feed && store.appState.feedState.showFilterMenu {