e2e: cover channel daemon lifecycle and stale PID safety

[codeaholicguy]

Current coverage

No E2E invokes channel start --daemon, channel status, or channel stop.

What is missing

• Detached bridge spawn and startup failure
• PID, log, and registry creation
• Duplicate bridge prevention and named bridge selection
• Status reconciliation between config, registry, and live process
• Stop signal, child termination, and registry cleanup
• Multiple bridges and stale/reused PID identity protection
• Concurrent registry updates

Risk ranking

Critical, rank 1: daemon control signals processes and persists shared state; the audit identified lossy registries and risk of terminating an unrelated reused PID.

Recommended E2E tests

• Launch a fake long-running CLI agent and bridge child in an isolated HOME, then assert daemon PID/log/registry, status, stop, and child termination.
• Seed the registry with a live unrelated PID plus mismatched start identity and assert channel stop refuses to signal it.

Acceptance criteria

• The checklist tests are merged under e2e/.
• Tests verify process identity, not PID existence alone.
• All children and registry fixtures are cleaned up after success or failure.

Related audit findings

A4 and C2: lossy JSON registry persistence. A7: stale daemon PID can target another process. A5: overlapping async polling affects a running bridge. D5: delivery queue/replay is a future extension.