[CBEPX]: Task 1 is ready for hosted validation in #61 (`04e606ac770edde2f3d7a85887988d7f29188c63`). Final Opus 5.5/high review approved. Parent verification passed: 1027 unit tests, 120 integration tests, 24 native Codex E2E tests, lint/typechecks, live Claude Stop boundary, candidate adversarial structured output, and actual stdio Git MCP staged/untracked qualification. No skips. The PR also keeps large/omitted changes reviewable without Bash: staged-only MCP diff, MCP-based fallback instructions, and complete untracked status regardless of user Git settings. All reproduced high/medium findings are resolved. CI and Mutation are running; merge remains pending their results. Task 2 follows after this part is accepted.

Context: GitHub issue CBEPX/cc-plugin-codex#60 (closed, 2 comments, reported 2026-09-25): Track selective Sendbird backports and tooling updates from the qualified v1.7.7 baseline (`66846d9080dd749dcc0b9ef9c37af8d5fd4cc203`). Ship one small PR per item, sequentially, with releases after local qualification of each wave. Owner: Codex coordinator with Claude through cc for planning, implementation, fresh review, verification analysis and release evidence review. Record exact source SHAs, requested/final models, cc job IDs, tests, CI and artifact readbacks below as work completes. ## Wave 1 , released v1.7.8 - [x] Stop-review through bundled Git MCP: exact read-only tool grants, st