v0.5.0 — ARMED handoff and codex collaboration

• ARMED-handoff transport: the codex wrapper launches codex in the background and ends its turn; the orchestrator owns the waiting through a background watcher (DONE / DIED / TIMEOUT) and messages the wrapper to relay. The wrapper busy-wait loop is gone.
• Pid-file liveness: the launch command records the codex pid and the watcher probes it with kill -0 — command-line pattern matching proved unreliable under host hooks that inject text into every shell's argv (falsified live before shipping).
• Codex collaboration dispatch: codex exec sessions expose collaboration.spawn_agent; codex reviewers dispatch auxiliary personas for real and record child ids. Execution-tier coverage still never satisfies final-fresh-exit — codex-side ids reach the orchestrator only as self-reported relay text, so the design-tier gate keeps its verifiable-dispatch rationale.
• Researcher personas rewritten as contracts (lens + negative space + output shape) in place of inherited phase choreography; the repository's own git history is repo evidence at every fresh-review boundary; adversarial review depth keys on consequence, not changed-line counts.
• cvg-work failing-first evidence now checks against the slice's parent commit — mechanically verifiable and compatible with one atomic commit per slice.
• Hybrid-transport smoke procedure documented (five legs, including the DIED path) after being run live end-to-end; wrapper-compliance eval rewritten two-phase, re-baselined 5/5.