fix(feat): prevent startup stall by waiting for Postgres/Redis and add healthcheck

[amirhmoradi]

What is this PR about?

Dokploy can start before Postgres/Redis in orchestrators like Docker Swarm, leading to a permanent stalled state where the process never recovers.

This PR adds a lightweight container entrypoint (docker-entrypoint.sh) that waits for real Postgres and Redis connectivity before starting Dokploy; using already available Node tools without introducing new installs in the image; and a Docker HEALTHCHECK that uses the existing /api/health endpoint.

No application code changes, no new runtime dependencies, opt-out via env var.

Environment variables

• DOKPLOY_WAIT_FOR_DEPS (default: 1)
  Enable or disable waiting for PostgreSQL and Redis before starting Dokploy.

• DOKPLOY_WAIT_TIMEOUT_SECONDS (default: 600)
  Maximum time (per dependency) to wait before exiting with error.

• DOKPLOY_WAIT_INTERVAL_SECONDS (default: 2)
  Delay between retry attempts.

• DATABASE_URL (required unless POSTGRES_URL is set)
  PostgreSQL connection string used for startup readiness checks.

• POSTGRES_URL (optional)
  Override PostgreSQL URL used only for startup readiness checks.

• REDIS_HOST (required)
  Redis hostname used by Dokploy and startup checks.

• REDIS_PORT (default: 6379)
  Redis port used for startup checks.

• REDIS_URL (optional)
  Override Redis connection URL used only for startup readiness checks.

Checklist

Before submitting this PR, please make sure that:

• You created a dedicated branch based on the canary branch.
• You have read the suggestions in the CONTRIBUTING.md file https://github.com/Dokploy/dokploy/blob/canary/CONTRIBUTING.md#pull-request
• You have tested this PR in your local instance.

Issues related (if applicable)

None

Screenshots (if applicable)

None