resolveSubagentSpawnContext and related lookups called client.session.get
without the query.directory parameter, causing project-scoped sessions
to 404 under newer OpenCode SDK versions. Threaded directory through
SpawnerContext/BackgroundManager so all four call-sites pass it.
🤖 Generated with OhMyOpenCode assistance
https://github.com/code-yeongyu/oh-my-opencode
- Check response.error and !response.data after session.get() to fail closed
- Prevents unlimited spawning when SDK returns non-throwing error responses
- Added regression tests for SDK error and missing data scenarios
YeonGyu-Kim