Add download link with pretty filename from document title

- servePDF now supports ?download=1 query param
- Looks up document title and uses it as the Content-Disposition filename
- Download button on document page triggers actual download (not tab open)
- Added sanitizeFilename helper for safe Content-Disposition values

main.go

@@ -275,6 +275,7 @@ func searchHandler(w http.ResponseWriter, r *http.Request) {
 
 func servePDF(w http.ResponseWriter, r *http.Request) {
 	hash := chi.URLParam(r, "hash")
+	download := r.URL.Query().Get("download") == "1"
 
 	// Try PDF first, then TXT
 	for _, ext := range []string{".pdf", ".txt"} {
@@ -285,6 +286,13 @@ func servePDF(w http.ResponseWriter, r *http.Request) {
 			} else {
 				w.Header().Set("Content-Type", "text/plain")
 			}
+			if download {
+				filename := hash + ext
+				if doc, err := GetDocument(hash); err == nil && doc.Title != "" {
+					filename = sanitizeFilename(doc.Title) + ext
+				}
+				w.Header().Set("Content-Disposition", fmt.Sprintf(`attachment; filename="%s"`, filename))
+			}
 			http.ServeFile(w, r, path)
 			return
 		}
@@ -293,6 +301,13 @@ func servePDF(w http.ResponseWriter, r *http.Request) {
 	// Try without extension
 	path := filepath.Join(storeDir, hash)
 	if _, err := os.Stat(path); err == nil {
+		if download {
+			filename := hash
+			if doc, err := GetDocument(hash); err == nil && doc.Title != "" {
+				filename = sanitizeFilename(doc.Title)
+			}
+			w.Header().Set("Content-Disposition", fmt.Sprintf(`attachment; filename="%s"`, filename))
+		}
 		http.ServeFile(w, r, path)
 		return
 	}
@@ -300,6 +315,12 @@ func servePDF(w http.ResponseWriter, r *http.Request) {
 	http.Error(w, "File not found", http.StatusNotFound)
 }
 
+// sanitizeFilename removes characters unsafe for use in Content-Disposition filenames.
+func sanitizeFilename(name string) string {
+	replacer := strings.NewReplacer(`"`, "'", "/", "-", "\\", "-", "\n", " ", "\r", "")
+	return replacer.Replace(name)
+}
+
 // API handlers
 
 func apiSearchHandler(w http.ResponseWriter, r *http.Request) {

templates/document.html

@@ -39,7 +39,7 @@
                 Share
             </button>
             {{if .Document.PDFPath}}
-            <a href="/pdf/{{.Document.ID}}" target="_blank" class="inline-flex items-center px-3 py-2 bg-brand-600 hover:bg-brand-700 text-white text-sm font-medium rounded-lg transition-all">
+            <a href="/pdf/{{.Document.ID}}?download=1" class="inline-flex items-center px-3 py-2 bg-brand-600 hover:bg-brand-700 text-white text-sm font-medium rounded-lg transition-all">
                 <svg class="w-4 h-4 mr-1.5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                     <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M12 10v6m0 0l-3-3m3 3l3-3m2 8H7a2 2 0 01-2-2V5a2 2 0 012-2h5.586a1 1 0 01.707.293l5.414 5.414a1 1 0 01.293.707V19a2 2 0 01-2 2z"></path>
                 </svg>