Improve OKX options sizing, expiry sync, and multi-position accordion UI.

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

lib/options/templates/options_panel.html

@@ -62,7 +62,7 @@
                     <div class="form-row options-order-mode-row">
                         <label><input type="radio" name="opt-size-mode" value="sheets" checked> 指定张数</label>
                         <input type="number" id="opt-sheets-amount" min="1" step="1" value="1" placeholder="张数">
-                        <label><input type="radio" name="opt-size-mode" value="budget_full"> 按单笔上限打满</label>
+                        <label><input type="radio" name="opt-size-mode" value="budget_full"> 按可用余额打满</label>
                         <label><input type="radio" name="opt-size-mode" value="eth_amount"> 指定币数量</label>
                         <input type="number" id="opt-eth-amount" min="0.01" step="0.01" placeholder="如 0.5" style="display:none">
                         <input type="text" id="opt-signal-note" placeholder="备注(关键位说明)">