Integrate retrieval into runtime

[TheGreenCedar]

Summary

• Integrates sidecar-primary retrieval into runtime search, packet orchestration, trace export, rollback policy, and semantic/query ranking surfaces.
• Extends API DTOs for retrieval shadow diagnostics and adds workspace inventory support.
• Adds eval probe catalog required by runtime packet tests.

Tests

• cargo check -p codestory-runtime
• cargo test -p codestory-runtime --test retrieval_eval
• cargo test -p codestory-runtime --test retrieval_primary_rejection
• cargo test -p codestory-runtime --lib
• cargo test -p codestory-contracts
• cargo fmt --check
• git diff --check

Stack

Base: codex/accuracy-pass-02-retrieval-sidecar (#12)
Next: codex/accuracy-pass-04-cli-retrieval