Add rendering routes and share UI to web server

The web UI was linking to /v1/ REST API paths that aren't served
through nginx. Added SVG/JPG/PDF rendering and share link endpoints
directly to the web server so everything works through port 443.

- Add render.go with SVG, JPG, PDF handlers for auth and share paths
- Register render routes and share management routes in web server
- Update template links from /v1/... to /notebooks/... paths
- Add share link creation, display, and revocation to notebook view

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

internal/webserver/handlers.go

@@ -128,15 +128,21 @@ func (ws *WebServer) handleNotebook(w http.ResponseWriter, r *http.Request) {
 		}
 		pages = append(pages, pageInfo{
 			Number:   num,
-			SVGLink:  fmt.Sprintf("/v1/notebooks/%d/pages/%d/svg", id, num),
+			SVGLink:  fmt.Sprintf("/notebooks/%d/pages/%d/svg", id, num),
 			ViewLink: fmt.Sprintf("/notebooks/%d/pages/%d", id, num),
 		})
 	}
 
+	// Load share links for this notebook.
+	shareLinks, _ := share.ListLinks(ws.db, id, ws.baseURL)
+
 	ws.render(w, "notebook.html", map[string]any{
-		"Title":   title,
-		"Pages":   pages,
-		"PDFLink": fmt.Sprintf("/v1/notebooks/%d/pdf", id),
+		"ID":         id,
+		"Title":      title,
+		"Pages":      pages,
+		"PDFLink":    fmt.Sprintf("/notebooks/%d/pdf", id),
+		"ShareLinks": shareLinks,
+		"BaseURL":    ws.baseURL,
 	})
 }
 
@@ -155,9 +161,9 @@ func (ws *WebServer) handlePage(w http.ResponseWriter, r *http.Request) {
 		"NotebookTitle": title,
 		"PageNumber":    num,
 		"BackLink":      fmt.Sprintf("/notebooks/%d", id),
-		"SVGLink":       fmt.Sprintf("/v1/notebooks/%d/pages/%d/svg", id, num),
-		"JPGLink":       fmt.Sprintf("/v1/notebooks/%d/pages/%d/jpg", id, num),
-		"PDFLink":       fmt.Sprintf("/v1/notebooks/%d/pdf", id),
+		"SVGLink":       fmt.Sprintf("/notebooks/%d/pages/%d/svg", id, num),
+		"JPGLink":       fmt.Sprintf("/notebooks/%d/pages/%d/jpg", id, num),
+		"PDFLink":       fmt.Sprintf("/notebooks/%d/pdf", id),
 	})
 }
 
@@ -202,6 +208,7 @@ func (ws *WebServer) handleShareNotebook(w http.ResponseWriter, r *http.Request)
 		"Title":   title,
 		"Pages":   pages,
 		"PDFLink": fmt.Sprintf("/s/%s/pdf", token),
+		"Shared":  true,
 	})
 }
 
@@ -228,6 +235,28 @@ func (ws *WebServer) handleSharePage(w http.ResponseWriter, r *http.Request) {
 	})
 }
 
+// --- Share management ---
+
+func (ws *WebServer) handleCreateShare(w http.ResponseWriter, r *http.Request) {
+	id, _ := strconv.ParseInt(chi.URLParam(r, "id"), 10, 64)
+	_, _, err := share.CreateLink(ws.db, id, 0, ws.baseURL) // no expiry
+	if err != nil {
+		slog.Error("create share link", "error", err)
+		http.Error(w, "Failed to create share link", http.StatusInternalServerError)
+		return
+	}
+	http.Redirect(w, r, fmt.Sprintf("/notebooks/%d", id), 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")
+	if token != "" {
+		_ = share.RevokeLink(ws.db, token)
+	}
+	http.Redirect(w, r, fmt.Sprintf("/notebooks/%d", id), http.StatusFound)
+}
+
 // --- auth middleware ---
 
 type ctxKey string