Document the first successful Docker evaluation

[brudex]

Proposed labels: documentation, area:docker, good first issue

Context

The development guide documents Docker Compose setup and health endpoints, but
an evaluator does not have one short, reproducible checklist for confirming a
successful web, jobs, and migration run.

Suggested starting points

• docs/development.md
• compose.yaml
• README.md (only if a brief link improves discoverability)

Scope

Add a concise post-start verification checklist with expected health responses,
a safe migration-status check, common symptoms, and cleanup guidance. Ensure
all commands use placeholders and never instruct readers to expose secrets.

Non-goals

• Do not change Docker images, Compose services, or environment-variable
  defaults.
• Do not add destructive database cleanup commands.

Acceptance criteria

• The guide explains how to verify the web service, job service, and database
  migration state after docker compose up.
• Expected success output and common failure symptoms are explicit.
• Commands are consistent with compose.yaml, avoid secrets, and include safe
  stop/cleanup guidance.
• The Compose configuration validates successfully.

Verification

1. Run docker compose config --quiet.
2. Review each command against compose.yaml and docs/development.md.
3. Run npm test if a repository script or documentation fixture changes.