Fix Codex companion staging and current protocol analysis

[minglong51]

Codex 0.155.1 looks for codex-code-mode-host beside its executable. The collector staged only the main binary, so the isolated app server could complete text turns while code-mode tools were unavailable. Stage the exact companion pinned to the reviewed primary/version pair, retaining descriptor-bound snapshots, checksum and mode checks, disk reservation, and cleanup of both owned files. The pinned Codex binary now fails early if its matching helper is absent or invalid.

Recognize current disabled remote-control, rate-limit, and thread-settings notifications in the offline analyzer. Count provider warnings without exposing their contents; active remote control and unknown messages still leave analysis partial. Qualification, task binding, source health, and all 24 matrix cells retain their existing unknown state.

Validation:

• All 122 existing tests and the 24-cell evidence check pass; no repository tests changed.
• 72 disposable scenario groups cover companion tampering/cleanup, metadata privacy/malformed input, and existing analyzer binding/replay behavior.
• Bounded native Codex captures verify a clean baseline, one input request opened/resolved, and one approval cancelled/resolved with the command declined without execution. All three parse completely with zero warnings; raw captures and credentials remain private.

Companion provenance: official Codex 0.155.1 release; the published archive digest and extracted helper checksum were verified. Persistent task-generation binding, heartbeat expiry, live duplicate/stale handling, reconnect, and unresolved-request recovery remain unproven and require the next adapter harness.