feat(签名展示): OFDGo WebUI支持签名展示

assets/webui/index.html

@@ -80,11 +80,22 @@
 						<dt>类型</dt>
 						<dd id="metaType">-</dd>
 					</div>
+					<div>
+						<dt>签名</dt>
+						<dd id="metaSignatures">0</dd>
+					</div>
 					<div>
 						<dt>字体</dt>
 						<dd id="metaFonts">0</dd>
 					</div>
 				</dl>
+				<section id="signaturePanel" class="signature-panel" aria-labelledby="signaturePanelTitle" hidden>
+					<div class="panel-row">
+						<div id="signaturePanelTitle" class="panel-title compact">签名</div>
+						<span id="signatureSummary" class="count-pill">0</span>
+					</div>
+					<div id="signatureList" class="signature-list"></div>
+				</section>
 				<section class="doc-font-panel" aria-labelledby="docFontPanelTitle">
 					<div class="panel-row">
 						<div id="docFontPanelTitle" class="panel-title compact">OFD 字体</div>