Add bootstrap scripts and restructure runbook

- scripts/run-bootstrap.sh: copies and runs the deploy user bootstrap on a
  fresh server, verifies SSH login, checks vault as a preflight step
- scripts/bootstrap-deploy-user.sh: runs on the server as root, accepts the
  SSH public key as an argument (read from keys/ by run-bootstrap.sh)
- scripts/check-vault.sh: decrypts vault.yml and verifies all 11 required
  secrets are present and non-empty
- docs/runbook.md: restructured into correct order (collections → DNS → vault
  → bootstrap → playbook), added scripts reference table, moved first-run
  notes for Gitea/Keycloak/registry into their own section
- README.md: added scripts/ to repo layout

scripts/check-vault.sh

@@ -0,0 +1,59 @@
+#!/usr/bin/env bash
+# Decrypts ansible/group_vars/vault.yml and checks all required secrets are present
+# and non-empty. Exits non-zero if any are missing.
+# Usage: bash scripts/check-vault.sh
+
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+REPO_ROOT="$(cd "${SCRIPT_DIR}/.." && pwd)"
+VAULT_FILE="${REPO_ROOT}/ansible/group_vars/vault.yml"
+
+REQUIRED_KEYS=(
+  traefik_dashboard_users
+  gitea_db_password
+  gitea_secret_key
+  gitea_internal_token
+  keycloak_db_password
+  keycloak_admin_password
+  nextcloud_db_password
+  nextcloud_admin_password
+  roundcube_db_password
+  roundcube_des_key
+  registry_htpasswd
+)
+
+if [ ! -f "${VAULT_FILE}" ]; then
+  echo "ERROR: vault file not found at ${VAULT_FILE}" >&2
+  echo "       Create it with: ansible-vault create ansible/group_vars/vault.yml" >&2
+  exit 1
+fi
+
+if ! command -v ansible-vault &>/dev/null; then
+  echo "ERROR: ansible-vault not found — install with: pip install ansible" >&2
+  exit 1
+fi
+
+echo "==> Decrypting vault (you will be prompted for the vault password)"
+VAULT_CONTENT=$(ansible-vault view "${VAULT_FILE}")
+
+MISSING=()
+for key in "${REQUIRED_KEYS[@]}"; do
+  # Match lines like:   key: "value"  or  key: value  — but not  key: ""  or  key: ''  or missing
+  if ! echo "${VAULT_CONTENT}" | grep -qE "^${key}:[[:space:]]+[^'\"[:space:]]|^${key}:[[:space:]]+['\"].+['\"]"; then
+    MISSING+=("${key}")
+  fi
+done
+
+if [ ${#MISSING[@]} -gt 0 ]; then
+  echo "" >&2
+  echo "ERROR: the following secrets are missing or empty in vault.yml:" >&2
+  for key in "${MISSING[@]}"; do
+    echo "       - ${key}" >&2
+  done
+  echo "" >&2
+  echo "Edit the vault with: ansible-vault edit ansible/group_vars/vault.yml" >&2
+  exit 1
+fi
+
+echo "    OK — all required secrets are present"