feat(KLEF-132): Removed hardcoding to only Minecraft and Kubernetes

[NathanRoos]

Pull Request

Summary

Replaced the hardcoded Kubernetes-only runtime with a universal RuntimeAdapter interface. The daemon now auto-detects whether to use Docker or Kubernetes at startup, verifying both are actually reachable before committing. A full Docker adapter was implemented alongside the unified Kubernetes adapter, making the daemon work locally without any cluster.

Related Issues

Closes #

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Changes

What's Included

• Universal RuntimeAdapter interface replacing the old hardcoded Kubernetes/Docker split
• Full Docker adapter: image pull, resource limits, persistent volumes, port mapping, container lifecycle
• Unified Kubernetes adapter: Deployment, StatefulSet, and Agones GameServer strategies in one file
• detectRuntime now pings Docker to verify it's reachable — won't silently fall back if Kubernetes is misconfigured
• Removed RuntimeMode config field — runtime is detected automatically
• Workers migrated from ServerOperationPayload to WorkloadSpec
• minecraft/vanilla blueprint and construct added to the crate registry

What's Not Included

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Testing

How Was This Tested?

• All worker unit tests updated and passing (go build ./... clean)
• Deployed a vanilla Minecraft GameServer to a live Kubernetes cluster via testprovision
• GameServer reached Ready state with ports allocated via Agones dynamic port policy
• Verified pod running with correct env vars, resource limits, and Agones sidecar
• Kubernetes: testprovision k8s — provisioned an Agones GameServer, confirmed it reached Ready state with ports allocated
• Docker: testprovision docker — provisioned a container locally, confirmed Minecraft 1.21.5 running and accessible on the allocated host port

Test Coverage

• Unit tests added or updated
• Integration tests added or updated
• Manually tested end-to-end

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Breaking Changes

Does this PR introduce breaking changes?

• Yes
• No

If yes, describe the impact and any required migration steps:

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Security Considerations

• This PR affects authentication or authorization logic
• This PR touches secrets, tokens, or environment variables
• This PR affects infrastructure, deployment pipelines, or network configuration

If any box is checked, describe the security impact and any mitigations applied:

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Documentation

Does this PR require documentation updates?

• Yes
• No

If yes, check all that apply:

• README.md
• ARCHITECTURE.md
• API reference
• Architecture diagrams (C4 / DDD)
• /docs

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UI/UX (If Applicable)

• Includes new components or views
• Changes styles or theme tokens
• Responsive behavior verified
• Requires design approval

Screenshots or recordings:

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Pre-Merge Checklist

• PR title follows semantic format (feat:, fix:, chore:, docs:, refactor:, test:)
• All CI checks passing
• Code follows project style guidelines
• No debug logs or commented-out code left in
• Dependencies reviewed (no unnecessary additions)
• No sensitive information included

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Reviewer Notes