Add notebook delete, fix button styling, rename Share button

- Add delete notebook handler with ownership check and CASCADE delete
- Rename "Create Share Link" to "Share"
- Fix action button heights: use inline-flex + align-items for
  consistent sizing across <a> and <button> elements

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

internal/webserver/handlers.go

@@ -248,6 +248,23 @@ func (ws *WebServer) handleCreateShare(w http.ResponseWriter, r *http.Request) {
 	http.Redirect(w, r, fmt.Sprintf("/notebooks/%d", id), http.StatusFound)
 }
 
+func (ws *WebServer) handleDeleteNotebook(w http.ResponseWriter, r *http.Request) {
+	userID := r.Context().Value(userIDKey).(int64)
+	id, _ := strconv.ParseInt(chi.URLParam(r, "id"), 10, 64)
+
+	// Verify ownership before deleting.
+	var ownerID int64
+	err := ws.db.QueryRow("SELECT user_id FROM notebooks WHERE id = ?", id).Scan(&ownerID)
+	if err != nil || ownerID != userID {
+		http.Error(w, "Not found", http.StatusNotFound)
+		return
+	}
+
+	// CASCADE deletes pages, strokes, and share_links.
+	_, _ = ws.db.Exec("DELETE FROM notebooks WHERE id = ?", id)
+	http.Redirect(w, r, "/notebooks", http.StatusFound)
+}
+
 func (ws *WebServer) handleRevokeShare(w http.ResponseWriter, r *http.Request) {
 	id, _ := strconv.ParseInt(chi.URLParam(r, "id"), 10, 64)
 	token := r.FormValue("token")

internal/webserver/server.go

@@ -112,6 +112,7 @@ func Start(cfg Config) (*http.Server, error) {
 		r.Get("/notebooks/{id}/pages/{num}/svg", ws.handlePageSVG)
 		r.Get("/notebooks/{id}/pages/{num}/jpg", ws.handlePageJPG)
 		r.Get("/notebooks/{id}/pdf", ws.handleNotebookPDF)
+		r.Post("/notebooks/{id}/delete", ws.handleDeleteNotebook)
 		r.Post("/notebooks/{id}/share", ws.handleCreateShare)
 		r.Post("/notebooks/{id}/share/revoke", ws.handleRevokeShare)
 		r.Get("/logout", ws.handleLogout)

web/templates/layout.html

@@ -18,9 +18,9 @@
         .grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); gap: 1rem; }
         .page-thumb { border: 1px solid #ccc; background: #fff; aspect-ratio: 0.773; display: flex; align-items: center; justify-content: center; }
         .page-thumb img { width: 100%; height: 100%; object-fit: contain; }
-        .btn { display: inline-block; padding: 0.5rem 1rem; border: 1px solid #111; border-radius: 4px; text-decoration: none; color: #111; background: #fff; cursor: pointer; }
+        .btn { display: inline-flex; align-items: center; padding: 0.5rem 1rem; border: 1px solid #111; border-radius: 4px; text-decoration: none; color: #111; background: #fff; cursor: pointer; font: inherit; font-size: 1rem; line-height: 1.5; box-sizing: border-box; }
         .btn:hover { background: #f0f0f0; }
-        .actions { display: flex; gap: 0.5rem; margin: 1rem 0; }
+        .actions { display: flex; align-items: center; gap: 0.5rem; margin: 1rem 0; }
         input[type="text"], input[type="password"] { padding: 0.5rem; border: 1px solid #ccc; border-radius: 4px; width: 100%; max-width: 300px; }
         label { display: block; margin-bottom: 0.25rem; font-weight: bold; }
         .form-group { margin-bottom: 1rem; }

web/templates/notebook.html

@@ -6,7 +6,11 @@
     <a href="{{.PDFLink}}" class="btn">Download PDF</a>
     {{if not .Shared}}
     <form method="POST" action="/notebooks/{{.ID}}/share" style="display:inline;">
-        <button type="submit" class="btn">Create Share Link</button>
+        <button type="submit" class="btn">Share</button>
+    </form>
+    <form method="POST" action="/notebooks/{{.ID}}/delete" style="display:inline;"
+          onsubmit="return confirm('Delete this notebook from the server?');">
+        <button type="submit" class="btn" style="color: #c62828; border-color: #c62828;">Delete</button>
     </form>
     {{end}}
 </div>