Add TCP/UDP port mapping support

- Add app_ports table for storing port mappings per app
- Add Port model with CRUD operations
- Add handlers for adding/deleting port mappings
- Add ports section to app detail template
- Update Docker client to configure port bindings when creating containers
- Support both TCP and UDP protocols

internal/handlers/app.go

@@ -121,6 +121,7 @@ func (h *Handlers) HandleAppDetail() http.HandlerFunc {
 		envVars, _ := application.GetEnvVars(request.Context())
 		labels, _ := application.GetLabels(request.Context())
 		volumes, _ := application.GetVolumes(request.Context())
+		ports, _ := application.GetPorts(request.Context())
 		deployments, _ := application.GetDeployments(
 			request.Context(),
 			recentDeploymentsLimit,
@@ -135,6 +136,7 @@ func (h *Handlers) HandleAppDetail() http.HandlerFunc {
 			"EnvVars":     envVars,
 			"Labels":      labels,
 			"Volumes":     volumes,
+			"Ports":       ports,
 			"Deployments": deployments,
 			"WebhookURL":  webhookURL,
 			"DeployKey":   deployKey,
@@ -685,6 +687,96 @@ func (h *Handlers) HandleVolumeDelete() http.HandlerFunc {
 	}
 }
 
+// HandlePortAdd handles adding a port mapping.
+func (h *Handlers) HandlePortAdd() http.HandlerFunc {
+	return func(writer http.ResponseWriter, request *http.Request) {
+		appID := chi.URLParam(request, "id")
+
+		application, findErr := models.FindApp(request.Context(), h.db, appID)
+		if findErr != nil || application == nil {
+			http.NotFound(writer, request)
+
+			return
+		}
+
+		parseErr := request.ParseForm()
+		if parseErr != nil {
+			http.Error(writer, "Bad Request", http.StatusBadRequest)
+
+			return
+		}
+
+		hostPort, containerPort, valid := parsePortValues(
+			request.FormValue("host_port"),
+			request.FormValue("container_port"),
+		)
+		if !valid {
+			http.Redirect(writer, request, "/apps/"+application.ID, http.StatusSeeOther)
+
+			return
+		}
+
+		protocol := request.FormValue("protocol")
+		if protocol != "tcp" && protocol != "udp" {
+			protocol = "tcp"
+		}
+
+		port := models.NewPort(h.db)
+		port.AppID = application.ID
+		port.HostPort = hostPort
+		port.ContainerPort = containerPort
+		port.Protocol = models.PortProtocol(protocol)
+
+		saveErr := port.Save(request.Context())
+		if saveErr != nil {
+			h.log.Error("failed to save port", "error", saveErr)
+		}
+
+		http.Redirect(writer, request, "/apps/"+application.ID, http.StatusSeeOther)
+	}
+}
+
+// parsePortValues parses and validates host and container port strings.
+func parsePortValues(hostPortStr, containerPortStr string) (int, int, bool) {
+	hostPort, hostErr := strconv.Atoi(hostPortStr)
+	containerPort, containerErr := strconv.Atoi(containerPortStr)
+
+	if hostErr != nil || containerErr != nil || hostPort <= 0 || containerPort <= 0 {
+		return 0, 0, false
+	}
+
+	return hostPort, containerPort, true
+}
+
+// HandlePortDelete handles deleting a port mapping.
+func (h *Handlers) HandlePortDelete() http.HandlerFunc {
+	return func(writer http.ResponseWriter, request *http.Request) {
+		appID := chi.URLParam(request, "id")
+		portIDStr := chi.URLParam(request, "portID")
+
+		portID, parseErr := strconv.ParseInt(portIDStr, 10, 64)
+		if parseErr != nil {
+			http.NotFound(writer, request)
+
+			return
+		}
+
+		port, findErr := models.FindPort(request.Context(), h.db, portID)
+		if findErr != nil || port == nil {
+			http.NotFound(writer, request)
+
+			return
+		}
+
+		deleteErr := port.Delete(request.Context())
+		if deleteErr != nil {
+			h.log.Error("failed to delete port", "error", deleteErr)
+		}
+
+		http.Redirect(writer, request, "/apps/"+appID, http.StatusSeeOther)
+	}
+}
+
 // formatDeployKey formats an SSH public key with a descriptive comment.
 // Format: ssh-ed25519 AAAA... upaas-2025-01-15-example.com.
 func formatDeployKey(pubKey string, createdAt time.Time, host string) string {