Add expiry profit estimate and remove chain quick-buy button.

Let users enter a target index in the order panel for estimated expiry P&L, and remove the redundant buy button from the options chain row.

Co-authored-by: Cursor <cursoragent@cursor.com>

tests/test_options_pricing.py

@@ -67,6 +67,21 @@ def test_option_moneyness():
     assert option_moneyness_label("otm") == "虚值"
 
 
+def test_estimate_expiry_profit_at_index():
+    from lib.options.options_pricing_lib import estimate_expiry_profit_at_index
+
+    # Call 1780, ask 12.2, 0.01 ETH, target 1793 -> (13-12.2)*0.01 = 0.008
+    p = estimate_expiry_profit_at_index(
+        opt_type="C", strike=1780, target_idx=1793, entry_px=12.2, eth_amount=0.01
+    )
+    assert p == 0.008
+    # OTM call loses premium
+    p2 = estimate_expiry_profit_at_index(
+        opt_type="C", strike=1780, target_idx=1770, entry_px=12.2, eth_amount=0.01
+    )
+    assert p2 == round(-12.2 * 0.01, 4)
+
+
 def test_format_quote_liquidity():
     from lib.options.options_pricing_lib import format_quote_liquidity