Phase 14: add Squad, Draft, Market, Events tabs to dashboard

Four new tabs complete the dashboard UI for all existing Core endpoints:

Squad — view active squad with per-player chemistry dots and team
chemistry bar (colour-coded green/amber/red).

Draft — start a session with difficulty selector, pick from 5 candidates
per slot through all 11 positions, see picks accumulate in real time,
reward shown on completion.

Market — browse NPC listings with live search filter, one-click buy,
sell own cards with price input, cancel own listings; Refresh button
repopulates NPC inventory via POST /market/refresh.

Events — list all data-driven events with active/inactive state, bonus
effects summary (score/coin multipliers, extra market cards, pack
discounts), Activate/Deactivate buttons.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

tests/proxy_test.rs

@@ -240,6 +240,10 @@ async fn test_dashboard_contains_key_sections() {
     assert!(html.contains("tab-objectives"), "objectives tab missing");
     assert!(html.contains("tab-division"), "division tab missing");
     assert!(html.contains("tab-champs"), "fut champs tab missing");
+    assert!(html.contains("tab-squad"), "squad tab missing");
+    assert!(html.contains("tab-draft"), "draft tab missing");
+    assert!(html.contains("tab-market"), "market tab missing");
+    assert!(html.contains("tab-events"), "events tab missing");
     assert!(html.contains("tab-notifications"), "notifications tab missing");
 }