Collapse field hints into a default-folded 规则说明 on strategy and runtime settings.

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

frontend/src/styles/app.css

@@ -472,6 +472,60 @@ input {
   line-height: 1.4;
 }
 
+.settings-rules {
+  margin: 4px 0 12px;
+  border: 1px solid var(--line);
+  border-radius: 8px;
+  background: var(--input);
+}
+
+.settings-rules-toggle {
+  appearance: none;
+  width: 100%;
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: 8px;
+  border: 0;
+  background: transparent;
+  color: var(--muted);
+  padding: 10px 12px;
+  font-size: 13px;
+  font-weight: 600;
+  cursor: pointer;
+  text-align: left;
+}
+
+.settings-rules-toggle:hover {
+  color: var(--text);
+}
+
+.settings-rules.open .settings-rules-toggle {
+  color: var(--text);
+  border-bottom: 1px solid var(--line);
+}
+
+.settings-rules-chevron {
+  color: var(--muted);
+  font-size: 12px;
+}
+
+.settings-rules-body {
+  padding: 10px 12px 12px;
+}
+
+.settings-rules-list {
+  margin: 0;
+  padding-left: 18px;
+  color: var(--muted);
+  font-size: 12px;
+  line-height: 1.55;
+}
+
+.settings-rules-list li + li {
+  margin-top: 6px;
+}
+
 .settings-actions {
   margin-top: 8px;
   display: flex;