[docs] Update Repo Mind Light AW documentation for 2026-06-05

[szabta89]

Summary

• Added documentation for query.soma as an embedding-free alternative local retrieval backend to query.graph_rag_zero in README.md schema notes and cost section.
• Added a comment block about query.soma to the shared workflow file (.github/workflows/shared/repo-mind-light.md) so agents composing workflows know the option exists.

Source Context

• Checked repo-mind-light-source/repo_mind_light/config.py: SomaConfig and QuerySourcesConfig define soma as an optional, mutually-exclusive alternative to graph_rag_zero with None default.
• Checked repo-mind-light-source/repo_mind_light/indexing/indexer.py: confirmed that when graph_rag_zero is None, GRZ indexing is skipped and Soma indexes its own corpus instead.
• query_pipeline_needs_embeddings returns False when graph_rag_zero is None, confirming Soma is embedding-free.
• Source CHANGELOG.md shows Soma was introduced in v0.10.0 and stabilised in v0.10.1.
• Soma binary is bundled in the Docker image via the vendor/soma/ Dockerfile stage.

Validation

• Cross-checked new notes against SomaConfig fields and QuerySourcesConfig._validate_single_local_retrieval_backend validator.
• Confirmed COPILOT_GITHUB_TOKEN is still required even with Soma because the chat model is always used for answer synthesis.
• No config field names were invented; all terms match the source schema.

Notes

• SomaConfig tuning fields (max_tokens, assembly, query_timeout_seconds, index_timeout_seconds) were omitted as internal knobs with sensible defaults.
• Wiki re-embedding note remains accurate for GRZ; Soma does not use embeddings, covered by the new notes.

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Warning

Protected Files — Push Permission Denied

This was originally intended as a pull request, but the patch modifies protected files. A human must create the pull request manually.

Protected files

• .github/workflows/shared/repo-mind-light.md

The push was rejected because GitHub Actions does not have workflows permission to push these changes, and is never allowed to make such changes, or other authorization being used does not have this permission.

Create the pull request manually

# Download the patch from the workflow run
gh run download 27009757246 -n agent -D /tmp/agent-27009757246

# Create a new branch
git checkout -b docs/soma-backend-2026-06-05-90e232b0ab5dd092 main

# Apply the patch (--3way handles cross-repo patches)
git am --3way /tmp/agent-27009757246/aw-githubnext-repo-mind-light-aw-docs-soma-backend-2026-06-05.patch

# Push the branch and create the pull request
git push origin docs/soma-backend-2026-06-05-90e232b0ab5dd092
gh pr create --title '[docs] Update Repo Mind Light AW documentation for 2026-06-05' --base main --head docs/soma-backend-2026-06-05-90e232b0ab5dd092 --repo githubnext/repo-mind-light-aw

Generated by Repo Mind Light AW Documentation Updater · ● 25.8M · ◷

• expires on Jun 12, 2026, 10:42 AM UTC