fix wrong ui

src/lib/components/FileHistoryPanel.svelte

@@ -27,13 +27,60 @@
     if (Number.isNaN(date.getTime())) return value;
     return new Intl.DateTimeFormat(undefined, { dateStyle: "medium", timeStyle: "short" }).format(date);
   }
+
+  function fileName(path: string): string {
+    return path.split("/").pop() ?? path;
+  }
+
+  function pathTooltip(node: HTMLElement, text: string) {
+    let el: HTMLDivElement | null = null;
+
+    function show(e: MouseEvent) {
+      if (!text || !text.includes("/")) return;
+      el = document.createElement("div");
+      el.className = "path-tooltip";
+      el.textContent = text;
+      document.body.appendChild(el);
+      move(e);
+    }
+
+    function move(e: MouseEvent) {
+      if (!el) return;
+      const tw = el.offsetWidth;
+      const left = Math.max(8, Math.min(e.clientX - tw / 2, window.innerWidth - tw - 8));
+      el.style.left = `${left}px`;
+      el.style.top  = `${e.clientY - 44}px`;
+    }
+
+    function hide() {
+      el?.remove();
+      el = null;
+    }
+
+    node.addEventListener("mouseenter", show);
+    node.addEventListener("mousemove", move);
+    node.addEventListener("mouseleave", hide);
+
+    return {
+      update(v: string) { text = v; },
+      destroy() {
+        hide();
+        node.removeEventListener("mouseenter", show);
+        node.removeEventListener("mousemove", move);
+        node.removeEventListener("mouseleave", hide);
+      },
+    };
+  }
 </script>
 
 <section class="panel grid grid-rows-[auto_1fr] overflow-hidden" aria-label="Selected file history">
   <div class="section-head">
-    <div class="min-w-0">
+    <div class="min-w-0 flex-1 overflow-hidden">
       <span class="eyebrow">{selectedExplorerLabel}</span>
-      <h2 class="mt-0.5 text-ink text-base font-bold leading-tight truncate">{selectedExplorerPath || "No file"}</h2>
+      <h2
+        class="mt-0.5 text-ink text-base font-bold leading-tight truncate"
+        use:pathTooltip={selectedExplorerPath}
+      >{selectedExplorerPath ? fileName(selectedExplorerPath) : "No file"}</h2>
     </div>
     <span class="pill pill-count flex-shrink-0">{fileHistory.length}</span>
   </div>