Pull understand-chat skill into project and reference it directly in SDLC skills — Closes #163

[conradbzura]

Summary

Add a local understand-chat skill definition at llms/skills/understand-chat.md and update all six SDLC lifecycle skills to reference it directly instead of invoking the external /understand-chat slash command from the understand-anything plugin. This removes the implicit plugin dependency and gives the project full control over the knowledge graph querying behavior used during SDLC stages.

Closes #163

Proposed changes

Add local understand-chat skill definition

Introduce llms/skills/understand-chat.md containing the complete skill definition for querying the .understand-anything/knowledge-graph.json knowledge graph. The skill includes graph structure reference documentation, efficient reading instructions, and a step-by-step workflow for searching nodes, following edges, reading layer context, and answering queries using the relevant subgraph.

Update SDLC skill references

Replace the invoke /understand-chat directive in all six SDLC skills (commit.md, implement.md, issue.md, pr.md, review.md, test.md) with read and follow llms/skills/understand-chat.md. Each change is a single-line substitution that points to the local skill file instead of the external slash command. No functional change to the querying behavior itself.

Test cases

N/A