docs: [#285] add Docker Compose topology refactoring plan

[josecelano]

Summary

This PR adds a comprehensive refactoring plan for moving Docker Compose topology logic from Tera templates to the Rust domain layer.

Closes #285

Changes

New Files

• docs/refactors/plans/docker-compose-topology-domain-model.md - Main refactoring plan (~1500 lines)
• docs/issues/285-docker-compose-topology-refactoring-plan.md - Issue specification

Modified Files

• docs/refactors/active-refactorings.md - Registered this refactoring as active

Plan Highlights

Domain Rules Analysis

• ~47 domain rules identified across 6 categories:
  • Network rules (NET-01 to NET-15)
  • Service dependency rules (DEP-01 to DEP-03)
  • Port exposure rules (PORT-01 to PORT-11)
  • Volume rules (VOL-01 to VOL-07)
  • Service inclusion rules (SVC-01 to SVC-05)
  • Aggregate invariants (INV-01 to INV-05)

3-Phase Implementation

1. Phase 0: Convert named volumes to bind mounts with BindMount domain type
2. Phase 1: Create Network enum for type-safe network management
3. Phase 2: Create DockerComposeTopology aggregate

Implementation Strategy

5 separate PRs planned:

PR	Scope
PR 1	ADR: Bind Mount Standardization
PR 2	BUG-01: Remove invalid template branch
PR 3	Phase 0: Bind mount foundation
PR 4	Phase 1: Network domain types
PR 5	Phase 2: Topology aggregate

Issues Discovered

• BUG-01: Template handles invalid "Grafana without Prometheus" case
• ISSUE-01: ADR grafana-integration-pattern.md recommends named volumes (will be superseded)
• ISSUE-03: ADR says Grafana has no healthcheck but template now has one

Checklist

• Pre-commit checks pass: ./scripts/pre-commit.sh
• Plan document is complete with all phases defined
• Domain rules are documented with test specifications
• Implementation strategy (PRs) is clear
• Bugs and inconsistencies discovered are documented
• Plan follows refactoring documentation conventions
• Plan is registered in active-refactorings.md
• All markdown linting passes

Notes

• This is a documentation-only PR for reviewing the plan
• The actual implementation will be tracked by a separate Epic issue after this plan is merged
• Once merged, the Epic issue will reference this plan as the source of truth

[josecelano]

ACK 858a564