merge(branch-b): data pipeline + rewards + training — B1-B5, C1-C6

feat(training): Phase C6 — ablations, training curves, readme finalization

feat(training): Phase C5 — evaluation harness, baselines, plots, readme table

feat(training): Phase C4 — GRPO training, SFT warmstart, rollout, custom trainer

feat(training): Phase C3 — SFT trajectory generator, env clients, mock env

feat(rewards): Phase C2 — composite reward, replay verifier, frozen weights

feat(rewards): Phase C1 — all 9 reward components implemented

feat(data): Phase B5 — corpus instantiation, HF publish, annotations

feat(data): Phase B4 — 7 ScenarioFamilyGenerators with archetype loading

feat(data): Phase B3 — failure clustering and archetype extraction

feat(branch-b): B2 GitHub Actions log mining — gh-CLI scraper, anonymizer, throttle, cache

feat(branch-b): B1 public dataset ingest — DeFlaker, iDFlakies, FlakeFlagger, LogHub loaders + CLI

feat(branch-a): A5 replay visualizer — static HTML/JS viewer mounted under /viz

feat(branch-a): A3 episode lifecycle — budget enforcement, terminal handling, payload truncation, trace serialization

feat(branch-a): A2 tool implementations — route 11 handlers to scenario.tool_outputs with cost charging

refactor(branch-a): A1 — adopt openenv-core MCPEnvironment + create_app for canonical OpenEnv compliance

feat(branch-a): A1 server scaffold — FastAPI /reset /step /state /mcp + 11 stub tool handlers

feat(phase-0): foundation — uv project, schemas, mocks, manifest, CI