调整表单组样式选择器，排除自定义选择类以避免样式冲突。

Author: SolonCode

soloncode-cli/src/main/resources/static/css/settings.css

@@ -83,7 +83,7 @@
 .form-row-3col .form-group { flex: 1; min-width: 0; }
 .form-group label { display: block; font-size: 12px; color: var(--text-secondary); margin-bottom: 4px; font-weight: 500; }
 .form-group .required { color: #ef4444; }
-.form-group input, .form-group select, .form-group textarea { width: 100%; padding: 8px 12px; border: 1px solid var(--border-color); border-radius: 8px; background: var(--bg-input-box); color: var(--text-primary); font-size: 13px; outline: none; transition: border-color 0.2s; font-family: inherit; box-sizing: border-box; }
+.form-group input, .form-group select:not(.form-select-custom), .form-group textarea { width: 100%; padding: 8px 12px; border: 1px solid var(--border-color); border-radius: 8px; background: var(--bg-input-box); color: var(--text-primary); font-size: 13px; outline: none; transition: border-color 0.2s; font-family: inherit; box-sizing: border-box; }
 .form-group input:focus, .form-group select:focus, .form-group textarea:focus { border-color: var(--accent); }
 .form-actions { display: flex; gap: 8px; justify-content: flex-end; margin-top: 16px; }
 .btn-primary { padding: 8px 20px; border: none; border-radius: 8px; background: var(--accent); color: #fff; font-size: 13px; cursor: pointer; transition: opacity 0.15s; }