Fix tab switching + $100K paper trading capital

Tab IDs now match JavaScript: tab-backtest instead of tab-bt.
Paper trading increased to $100,000 ($10K per strategy, $30K reserve).
Server default paper metrics updated to $100K.

dashboard/server.py

@@ -86,7 +86,7 @@ def read_paper_metrics() -> dict:
                 return json.load(f)
     except (json.JSONDecodeError, IOError):
         pass
-    return {"status": "waiting", "mode": "paper", "strategies": {}, "trades": [], "equity_history": [], "total_pnl": 0, "total_equity": 5000}
+    return {"status": "waiting", "mode": "paper", "strategies": {}, "trades": [], "equity_history": [], "total_pnl": 0, "total_equity": 100000}
 
 
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