Shorten force-close window to 5m and grey-out open during blocks.

Unify Gate/OKX/Binance: disable the open button with a side note during force-close, cooloff, and daily freeze, and enforce the same gate server-side.

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

lib/common/static/form_submit_guard.js

@@ -35,7 +35,8 @@
         delete form.dataset.submitGuard;
         form.classList.remove("is-form-submitting");
         submitButtons(form).forEach(function (btn) {
-            btn.disabled = false;
+            // 风控灰显(开仓门禁)保持禁用
+            btn.disabled = btn.classList.contains("is-blocked");
             var orig = btn.dataset.submitGuardOrig;
             if (orig !== undefined) {
                 if (btn.tagName === "BUTTON") btn.textContent = orig;