feat: Enhance portfolio overview with dynamic value calculation and cash balance input

src/pages/journal/trading_journal_page.py

@@ -235,19 +235,53 @@ def trading_journal_page():
             # Portfolio overview section
             st.subheader("Portfolio Overview")
             col1, col2, col3 = st.columns(3)
-            
+
+            # Get cash balance
+            latest_portfolio = get_latest_portfolio_value()
+            cash_balance = latest_portfolio['cash_balance'] if latest_portfolio else 0
+
+            # Calculate total invested value and paper P/L
+            total_invested_value = 0
+            total_paper_pl = 0
+            if open_summary:
+                for summary in open_summary:
+                    ticker = summary['ticker']
+                    current_price = current_prices.get(ticker, 0)
+                    shares = summary['total_shares']
+                    avg_entry = summary['avg_entry_price']
+                    
+                    position_value = current_price * shares
+                    total_invested_value += position_value
+                    total_paper_pl += (current_price - avg_entry) * shares
+
+            # Calculate total portfolio value
+            total_portfolio_value = cash_balance + total_invested_value
+
             with col1:
-                st.metric("Total Portfolio Value", f"${total_portfolio_value:,.2f}")
-                st.metric("Cash Balance", f"${cash_balance:,.2f}", 
-                         f"{(cash_balance/total_portfolio_value)*100:.1f}% of Portfolio" if total_portfolio_value > 0 else "")
-            
+                # Add input for cash balance
+                new_cash_balance = st.number_input(
+                    "Cash Balance ($)", 
+                    value=cash_balance,
+                    step=100.0,
+                    format="%.2f"
+                )
+                
+                if new_cash_balance != cash_balance:
+                    # Update cash balance if changed
+                    update_portfolio_value(total_portfolio_value, new_cash_balance)
+                    st.rerun()
+
+                st.metric("Total Portfolio Value", 
+                         f"${total_portfolio_value:,.2f}",
+                         f"${total_paper_pl:,.2f} P/L" if total_paper_pl != 0 else None)
+
             with col2:
                 # Weekly metrics
                 weekly_pl_pct = (weekly_metrics['weekly_pl'] / total_portfolio_value * 100) if total_portfolio_value > 0 else 0
                 st.metric("Week P/L", 
                          f"${weekly_metrics['weekly_pl']:,.2f}",
                          f"{weekly_pl_pct:.2f}% | {weekly_metrics['weekly_trade_count']} trades")
-            
+
             with col3:
                 # Overall P/L metrics (from trade history)
                 total_pl = sum(trade.get('position_pl', 0) for trade in trade_history) if trade_history else 0