~anthropic/claude-sonnet-latest → B (6:4)

B fixes a concrete performance bug (scan was doing a full reducer replay including rank centrality, which is slow) with a single-pass parse check, adds a genuinely useful debugging tool (compile --ingest) with tests, and improves error surfacing without removing existing coverage. A delivers a real SSE-streaming improvement for fetch UX, but it also strips out three existing unit tests without replacement and pads the reddit worker with a large volume of tracing::debug! calls that add noise more than lasting design value.