recipes: Clean up incomplete recipes and clarify Kubernetes-only focus

Remove incomplete model directories and non-Kubernetes configurations to
streamline the recipes directory for production Kubernetes deployments.

Changes:
- Remove 5 incomplete model directories (deepseek-r1-distill-llama-8b,
  gemma3, llama4, qwen2-vl-7b-instruct, qwen3) that lack proper
  Kubernetes deployment manifests
- Delete run.sh script (non-Kubernetes automation tool)
- Remove standalone engine config YAMLs from deepseek-r1/trtllm that
  were not wrapped in Kubernetes manifests
- Document incomplete gpt-oss-120b disagg recipe with README explaining
  missing components

README improvements:
- Restructure Available Recipes table with 'Deployment' and 'Benchmark
  Recipe' columns to clarify that perf.yaml files are tools for users
  to run benchmarks, not published performance results
- Add comprehensive quick start guide with prerequisites
- Link to correct Kubernetes deployment guides
- Add troubleshooting section
- Remove extraneous links (docs.nvidia.com, license section)

Result: 4 models with 10 complete deployment recipes (7 with benchmark
scripts), focused exclusively on Kubernetes deployments.

Signed-off-by: Ben Hamm <[email protected]>