./launcher rebuild app error: bootstrap failed with exit code 234

Thanks for all the support, unfortunately it does not solve the problem.

For new users maybe worth to add a:

  1. enter container (e.g., ./launcher enter app

So I did. And pnp was already installed:

root@vtdiscourse-app:/var/www/discourse# pnpm --version
9.5.0

I already did, as written in my post above, without solving the problem.

Discourse was installed in April 2023.
I did upgrade successfully up (and including) to v3.4.0.beta3.
As written above, the OS is a LXC container, using Debian bullseye with latest updates installed.

The only installed extension is the Private Topics Plugin (still under maintenance and also kept up to date with each discourse update on my side).

Here we go:

## this is the all-in-one, standalone Discourse Docker container template
##
## After making changes to this file, you MUST rebuild
## /var/discourse/launcher rebuild app
##
## BE *VERY* CAREFUL WHEN EDITING!
## YAML FILES ARE SUPER SUPER SENSITIVE TO MISTAKES IN WHITESPACE OR ALIGNMENT!
## visit http://www.yamllint.com/ to validate this file as needed

templates:
  - "templates/postgres.template.yml"
  - "templates/redis.template.yml"
  - "templates/web.template.yml"
  ## Uncomment the next line to enable the IPv6 listener
  #- "templates/web.ipv6.template.yml"
  - "templates/web.ratelimited.template.yml"
  ## Uncomment these two lines if you wish to add Lets Encrypt (https)
  ##- "templates/web.ssl.template.yml"
  - "templates/web.ssl.template.yml"
  #- "templates/web.letsencrypt.ssl.template.yml"

## which TCP/IP ports should this container expose?
## If you want Discourse to share a port with another webserver like Apache or nginx,
## see https://meta.discourse.org/t/17247 for details
expose:
  - "80:80"   # http
  - "443:443" # https

params:
  db_default_text_search_config: "pg_catalog.english"

  ## Set db_shared_buffers to a max of 25% of the total memory.
  ## will be set automatically by bootstrap based on detected RAM, or you can override
  #db_shared_buffers: "128MB"
  db_shared_buffers: "256MB"

  ## can improve sorting performance, but adds memory usage per-connection
  #db_work_mem: "40MB"

  ## Which Git revision should this container use? (default: tests-passed)
  #version: tests-passed

env:
  LC_ALL: en_US.UTF-8
  LANG: en_US.UTF-8
  LANGUAGE: en_US.UTF-8
  # DISCOURSE_DEFAULT_LOCALE: en

  ## How many concurrent web requests are supported? Depends on memory and CPU cores.
  ## will be set automatically by bootstrap based on detected CPUs, or you can override
  UNICORN_WORKERS: 2

  ## TODO: The domain name this Discourse instance will respond to
  ## Required. Discourse will not work with a bare IP number.
  #DISCOURSE_HOSTNAME: 'discourse.example.com'
  DISCOURSE_HOSTNAME: 'my-discourse-domain.example.com'

  ## Uncomment if you want the container to be started with the same
  ## hostname (-h option) as specified above (default "$hostname-$config")
  #DOCKER_USE_HOSTNAME: true

  ## TODO: List of comma delimited emails that will be made admin and developer
  ## on initial signup example 'user1@example.com,user2@example.com'
  #DISCOURSE_DEVELOPER_EMAILS: 'me@example.com,you@example.com'
  DISCOURSE_DEVELOPER_EMAILS: 'my-admin-mail@example.com'

  ## TODO: The SMTP mail server used to validate new accounts and send notifications
  # SMTP ADDRESS, username, and password are required
  # WARNING the char '#' in SMTP password can cause problems!
  #DISCOURSE_SMTP_ADDRESS: smtp.example.com
  DISCOURSE_SMTP_ADDRESS: my-smtp-server.example.com
  #DISCOURSE_SMTP_PORT: 587
  #DISCOURSE_SMTP_USER_NAME: user@example.com
  DISCOURSE_SMTP_USER_NAME: my-user@my-smtp-server.example.com
  #DISCOURSE_SMTP_PASSWORD: pa$$word
  DISCOURSE_SMTP_PASSWORD: foo(obviously not)
  #DISCOURSE_SMTP_ENABLE_START_TLS: true           # (optional, default true)
  #DISCOURSE_SMTP_DOMAIN: discourse.example.com    # (required by some providers)
  ##DISCOURSE_NOTIFICATION_EMAIL: noreply@discourse.example.com    # (address to send notifications from)
  DISCOURSE_NOTIFICATION_EMAIL: my-user@my-smtp-server.example.com    # (address to send notifications from)

  ## If you added the Lets Encrypt template, uncomment below to get a free SSL certificate
  #LETSENCRYPT_ACCOUNT_EMAIL: me@example.com

  ## The http or https CDN address for this Discourse instance (configured to pull)
  ## see https://meta.discourse.org/t/14857 for details
  #DISCOURSE_CDN_URL: https://discourse-cdn.example.com
  
  ## The maxmind geolocation IP address key for IP address lookup
  ## see https://meta.discourse.org/t/-/137387/23 for details
  ##DISCOURSE_MAXMIND_LICENSE_KEY: 1234567890123456
  DISCOURSE_MAXMIND_LICENSE_KEY: my-key

## The Docker container is stateless; all data is stored in /shared
volumes:
  - volume:
      host: /var/discourse/shared/standalone
      guest: /shared
  - volume:
      host: /var/discourse/shared/standalone/log/var-log
      guest: /var/log

## Plugins go here
## see https://meta.discourse.org/t/19157 for details
hooks:
  after_code:
    - exec:
        cd: $home/plugins
        cmd:
          - git clone https://github.com/discourse/docker_manager.git
          - git clone https://github.com/communiteq/discourse-private-topics.git

## Any custom commands to run after building
run:
  - exec: echo "Beginning of custom commands"
  ## If you want to set the 'From' email address for your first registration, uncomment and change:
  ## After getting the first signup email, re-comment the line. It only needs to run once.
  #- exec: rails r "SiteSetting.notification_email='info@unconfigured.discourse.org'"
  - exec: echo "End of custom commands"

Any help appreciated.