feat: add helmfile-based deployment with multi-namespace support

[kirgene]

Prototype for mojaloop/design-authority-project#150

Replaces the mojaloop umbrella chart orchestration with helmfile. Each chart becomes an independent Helm release with its own namespace, dependency ordering, and rollback scope.

No chart changes. All existing subcharts, templates, and Docker images stay as-is.

Files

File	Purpose
helmfile.yaml.gotmpl	18 releases across 7 namespaces with dependency ordering
defaults.yaml	Shared infrastructure config (Kafka, MySQL, MongoDB, hub), ~130 lines
namespaces.yaml	Default multi-namespace layout
namespaces-single.yaml	Single-namespace override for backward compat
release-matrix.yaml	Chart version pins
examples/deployment.yaml	Example user config for customization

Try it

# List releases with namespaces and deps (no cluster needed)
helmfile -f helmfile.yaml.gotmpl list

# Single namespace mode
helmfile -f helmfile.yaml.gotmpl -e single-namespace list

# Custom deployment config
helmfile -f helmfile.yaml.gotmpl --state-values-file my-deployment.yaml list

What this solves

• Multi-namespace deployment (11 namespaces by default, configurable)
• Cross-chart value sharing without 13K-line values.yaml
• Dependency ordering via needs:
• Per-chart user overrides via --state-values-file
• Independent chart lifecycle (update one chart without re-releasing everything)

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud