Add GitHub star link

Author: xxllovemkm

web/src/App.jsx

@@ -156,6 +156,11 @@ export default function App() {
     <div className="app">
       <div className="page-inner">
         <header className="app-header">
+          <a className="repo-star" href="https://github.com/OpenRaiser/Gewu"
+            target="_blank" rel="noreferrer" aria-label="在 GitHub 上 Star Gewu">
+            <span className="repo-star-icon">★</span>
+            <span>Star</span>
+          </a>
           <div className="seal" aria-label="格物致知">
             <span>格</span><span>物</span>
             <span>致</span><span>知</span>

web/src/styles.css

@@ -98,6 +98,43 @@ html, body {
   letter-spacing: 3px;
   margin-top: 6px;
 }
+.repo-star {
+  position: absolute;
+  top: 2px;
+  right: 86px;
+  display: inline-flex;
+  align-items: center;
+  gap: 5px;
+  min-height: 30px;
+  padding: 4px 11px;
+  border: 1px solid rgba(107,58,46,0.55);
+  border-radius: 3px;
+  background: rgba(228,214,186,0.68);
+  color: var(--ink-soft);
+  font-family: var(--mono);
+  font-size: 12.5px;
+  line-height: 1;
+  letter-spacing: 0;
+  text-decoration: none;
+  box-shadow: 0 1px 0 rgba(255,255,255,0.28) inset;
+  transition: color .18s, border-color .18s, background .18s;
+}
+.repo-star:hover {
+  background: var(--paper-2);
+  border-color: var(--cinnabar);
+  color: var(--cinnabar);
+}
+.repo-star-icon {
+  color: var(--gold);
+  font-size: 14px;
+  line-height: 1;
+}
+@media (max-width: 860px) {
+  .repo-star {
+    left: 6px;
+    right: auto;
+  }
+}
 /* 朱砂印章 */
 .seal {
   position: absolute;