fix: instance link includes domain, project delete cleans up containers and proxies

- InstanceCard appends settings domain to subdomain link (stage-dev-app.example.com instead of just stage-dev-app)
- Project deletion now removes Docker containers and proxy routes before deleting DB records
- Pass domain from settings to InstanceCard via project detail page

internal/api/projects.go

@@ -169,6 +169,26 @@ func (s *Server) updateProject(w http.ResponseWriter, r *http.Request) {
 // deleteProject handles DELETE /api/projects/{id}.
 func (s *Server) deleteProject(w http.ResponseWriter, r *http.Request) {
 	id := chi.URLParam(r, "id")
+
+	// Clean up Docker containers and proxy routes before deleting the project.
+	ctx := r.Context()
+	stages, _ := s.store.GetStagesByProjectID(id)
+	for _, stage := range stages {
+		instances, _ := s.store.GetInstancesByStageID(stage.ID)
+		for _, inst := range instances {
+			if inst.ContainerID != "" {
+				if err := s.docker.RemoveContainer(ctx, inst.ContainerID, true); err != nil {
+					slog.Warn("delete project: remove container", "container", inst.ContainerID, "error", err)
+				}
+			}
+			if inst.ProxyRouteID != "" {
+				if err := s.proxyProvider.DeleteRoute(ctx, inst.ProxyRouteID); err != nil {
+					slog.Warn("delete project: delete proxy route", "route", inst.ProxyRouteID, "error", err)
+				}
+			}
+		}
+	}
+
 	if err := s.store.DeleteProject(id); err != nil {
 		if errors.Is(err, store.ErrNotFound) {
 			respondNotFound(w, "project")