feat(agent-orchestrator): lock down bridge and normalize audit logs

[Coldaine]

Summary

• replace the deprecated bridge's ad hoc action logging with canonical structured audit events, including nested subprocess records
• lock down alas_call_tool(...) behind an allowlist plus explicit ALAS_ALLOW_UNSAFE_STATE_MACHINE_CALLS=1 override
• update tests and docs to reflect the ADB-backed adb_tap contract and the blocked-by-default bridge policy

Why

The deprecated agent_orchestrator surface was still too open and its logs were flatter than the canonical adb_vision surface. This makes the deprecated path explicit, constrained, and reviewable instead of a generic remote tool trampoline.

Validation

• cd agent_orchestrator && uv run pytest test_alas_mcp.py test_mcp_audit.py test_integration_mcp.py -q
• cd adb_vision && uv run pytest test_server.py test_tool_audit.py -q

Stack

• base PR: feat(adb-vision): restore live piloting and audit backend helpers