Local deploy fails with cryptic 'unexpected end of JSON input' when Docker daemon not running

[vsilent]

Description

When Docker daemon is not running, stacker deploy --target local fails with a cryptic error:

unable to get image 'postgres:16-alpine': unexpected end of JSON input

This error doesn't help the user understand that Docker daemon is the issue.

Affected Projects

ArchiveBox, AstrBot, activepieces, aptabase, bitmagnet, metabase, middleware

Steps to Reproduce

1. Stop Docker daemon
2. Run stacker deploy --target local --force-rebuild
3. Observe cryptic JSON parse error

Expected Behavior

A clear pre-flight check error:

Error: Docker daemon is not running. Please start Docker Desktop or the Docker service and retry.

Actual Behavior

Cryptic JSON parse error from docker compose when it cannot reach the daemon.

Environment

• OS: macOS, Linux
• Docker version: 28.0.4
• Stacker CLI version: latest