trek: seed default admin, fix install and hooks

Seed a default admin account and harden the installer; update symlink behavior and LXC hook argument handling.

- Install: downgrade Node setup to 22, write ADMIN_EMAIL/ADMIN_PASSWORD into /opt/trek/server/.env for initial boot, chmod the file, wait for app health, then remove plaintext creds from the env and print the default admin credentials. Remove previous DB patching script and credentials file generation. Add health-check failure handling.
- ct/trek.sh: check for /opt/trek instead of ~/.trek, run npm ci without --production, and recreate server data/uploads by removing any existing dirs and creating explicit symlinks.
- Installer: mirror symlink strategy used in the container (rm then ln -s) and ensure generated ENCRYPTION_KEY note; add ADMIN_EMAIL default.
- json: set default username to admin@trek.local, update notes about seeded admin, ENCRYPTION_KEY storage, and APP_URL recommendation.
- tools/pve/lxc-prehook.sh: fix append_unique_line_in_ct to pass positional arguments into the bash -c snippet safely (avoid parent-shell expansion).

These changes ensure a reproducible default admin creation flow without leaving plaintext credentials, improve symlink handling, and fix a bug in the LXC prehook.

vm/k3s-vm.sh

@@ -23,6 +23,7 @@ METHOD=""
 NSAPP="Debian 12 VM"
 var_os="debian"
 var_version="12"
+INSTALL_ARGOCD_BOOTSTRAP="${INSTALL_ARGOCD_BOOTSTRAP:-1}"
 
 THIN="discard=on,ssd=1,"
 set -e
@@ -380,6 +381,57 @@ virt-customize -q -a "${FILE}" \
 
 msg_ok "Added in Image K3s, Helm & k9s"
 
+if [[ "$INSTALL_ARGOCD_BOOTSTRAP" == "1" ]]; then
+  msg_info "Add in Image ArgoCD Bootstrap"
+  virt-customize -q -a "${FILE}" \
+    --run-command 'mkdir -p /usr/local/sbin /etc/systemd/system /var/lib' \
+    --run-command 'cat <<"EOF" >/usr/local/sbin/bootstrap-argocd.sh
+#!/usr/bin/env bash
+set -euo pipefail
+
+export KUBECONFIG=/etc/rancher/k3s/k3s.yaml
+
+for _ in $(seq 1 120); do
+  if kubectl get nodes --no-headers 2>/dev/null | grep -q " Ready "; then
+    break
+  fi
+  sleep 2
+done
+
+if ! kubectl get nodes --no-headers 2>/dev/null | grep -q " Ready "; then
+  echo "K3s is not ready yet"
+  exit 1
+fi
+
+kubectl create namespace argocd --dry-run=client -o yaml | kubectl apply -f -
+kubectl apply -n argocd -f https://raw.githubusercontent.com/argoproj/argo-cd/stable/manifests/install.yaml
+kubectl -n argocd rollout status deploy/argocd-server --timeout=10m
+
+touch /var/lib/argocd-bootstrap.done
+EOF' \
+    --run-command 'chmod +x /usr/local/sbin/bootstrap-argocd.sh' \
+    --run-command 'cat <<"EOF" >/etc/systemd/system/argocd-bootstrap.service
+[Unit]
+Description=ArgoCD Bootstrap
+After=network-online.target k3s.service
+Wants=network-online.target
+ConditionPathExists=!/var/lib/argocd-bootstrap.done
+
+[Service]
+Type=oneshot
+ExecStart=/usr/local/sbin/bootstrap-argocd.sh
+RemainAfterExit=yes
+
+[Install]
+WantedBy=multi-user.target
+EOF' \
+    --run-command 'systemctl enable argocd-bootstrap.service' >/dev/null
+
+  msg_ok "Added in Image ArgoCD Bootstrap"
+else
+  msg_info "Skipping ArgoCD Bootstrap (INSTALL_ARGOCD_BOOTSTRAP=$INSTALL_ARGOCD_BOOTSTRAP)"
+fi
+
 msg_ok "Created a Debian 12 VM ${CL}${BL}(${HN})"
 if [ "$START_VM" == "yes" ]; then
   msg_info "Starting Debian 12 VM"