Fix strategy roll page JS broken by Jinja in static file.

Pass trading_session via inline page config, restore roll preview/execute handlers, and validate new stop-loss before preview.

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

modules/web/templates/strategy.html

@@ -138,7 +138,9 @@
             <div id="roll-preview" class="strategy-preview" hidden></div>
             <p class="hint" id="roll-exec-hint" hidden style="font-size:.75rem;margin-top:.45rem">市价加仓：须交易时段内确认，10 秒倒计时执行；突破加仓：休盘也可提交，开盘后再监控触价</p>
             {% if not trading_session %}
-            <p class="hint text-muted" id="roll-off-session-hint" style="font-size:.75rem;margin-top:.35rem">当前{{ session_clock.status_label or '休盘' }}：请选「突破加仓」填写突破价后预览并提交监控。</p>
+            <p class="hint text-muted" id="roll-off-session-hint" style="font-size:.75rem;margin-top:.35rem">当前{{ session_clock.status_label or '休盘' }}：市价加仓须交易时段内执行；休盘可先预览，或选「突破加仓」提交监控。</p>
+            {% else %}
+            <p class="hint text-muted" id="roll-off-session-hint" hidden style="font-size:.75rem;margin-top:.35rem"></p>
             {% endif %}
         </form>
         {% else %}
@@ -211,5 +213,10 @@
 </div>
 {% endblock %}
 {% block extra_js %}
+<script>
+window.STRATEGY_PAGE = {
+    inTradingSession: {{ 'true' if trading_session else 'false' }}
+};
+</script>
 <script src="{{ url_for('static', filename='js/strategy.js') }}"></script>
 {% endblock %}