Extend spawn test coverage with verification of Codex session correlation
mechanisms:
Pending spawn registry tests:
- _write_pending_spawn creates JSON file with correct spawn_id,
project_path, agent_type, and timestamp
- _cleanup_stale_pending_spawns removes files older than PENDING_SPAWN_TTL
while preserving fresh files
Session timestamp parsing tests:
- Handles ISO 8601 with Z suffix (Zulu time)
- Handles ISO 8601 with explicit +00:00 offset
- Returns None for invalid format strings
- Returns None for empty string input
These tests ensure spawn_id correlation works correctly for Codex
sessions, which don't have direct environment variable injection like
Claude sessions do.
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Position the spawn modal directly under the 'New Agent' button without a
blur overlay. Uses click-outside dismissal and absolute positioning.
Reduces visual disruption for quick agent spawning.
