v0.4.0 — feature expansion

[0.4.0] - 2026-06-13

Feature expansion. No breaking changes.

Added

• Multi-service commands — pass several service names
  (dctl restart web db api) or --all to act on every registered service.
  Services run in turn; one failure neither aborts the batch nor leaks state
  (each runs in an isolated subshell), and a summary reports any failures with
  a non-zero exit. exec, logs, and config remain single-service.
• --dry-run / -n — print the compose plan and hooks (location, files,
  arguments) without executing anything, prune included. Combines with
  multi-service to preview a whole batch.

Changed

• Command execution was extracted into dispatch_command() so it can run
  per-service. Single-service and current-directory behavior is unchanged.
• Multi-service restart skips the trailing logs -f (following the first
  service's logs would block the rest); single-service restart still follows.