Add a GB300 EKS Ubuntu training Slurm recipe

[mchmarny]

Feature summary

Add a public leaf recipe for GB300 + EKS + Ubuntu + training + Slurm, following the existing GB300 training and Slurm recipe patterns.

Problem and use case

AICR has a GB300 EKS Ubuntu training recipe and GB200 Slurm recipes, but no GB300 EKS Ubuntu training Slurm combination. Operators therefore cannot resolve this supported intent directly and must assemble an untracked configuration.

Proposed solution

Add a recipe that resolves from:

• service: eks
• accelerator: gb300
• os: ubuntu
• intent: training
• platform: slurm

The recipe should:

• use AICR's current public component pins
• retain the standalone NFD architecture and keep GPU Operator's embedded NFD disabled
• define the Slurm, topology, storage, and accounting choices required for this combination
• keep provider infrastructure configuration outside the recipe
• compose existing bases and mixins where possible rather than duplicating values

Success criteria

• The criteria query resolves exactly one GB300 EKS Ubuntu training Slurm recipe.
• The resolved component graph uses current, verified AICR pins.
• Required value overrides and health checks are represented declaratively.
• Recipe resolution, validation, bundle generation, and deterministic-render tests pass.
• KWOK coverage is added and hardware-backed UAT is tracked with Add UAT coverage for Slurm/Slinky recipes (incl. topograph) #2358.
• Component catalog, recipe documentation, and generated BOM are updated where applicable.
• Unsupported infrastructure prerequisites are documented rather than provisioned by AICR.

Operational considerations

Any required scheduler or topology dependency fix must be consumed as a pinned, verified release. Recipe-time overrides cannot repair a dependency compiled into an upstream binary.