v0.2.0rc1

0.2.0rc1 — Architecture overhaul

First release candidate for 0.2.0. Major refactor of the backend, queue, activity, and worker systems.

Breaking changes

• agentexec.state.redis_backend → agentexec.state.redis (update AGENTEXEC_STATE_BACKEND if set explicitly)
• AGENTEXEC_QUEUE_NAME → AGENTEXEC_QUEUE_PREFIX (old name still accepted as alias)
• Activity functions are now async (await ax.activity.create(...), await ax.activity.update(...), etc.)
• Task.context is now Mapping[str, Any] (raw dict), not a typed BaseModel — hydration happens at execution time
• Task.create() is now async
• Removed: set_global_session/get_global_session/remove_global_session — use configure_engine/get_session
• Removed: state.backend.publish/subscribe (pubsub), index_add/index_range/index_remove, clear, configure

New features

• Partitioned Redis queues — tasks with lock_key route to dedicated partition queues with per-partition locking and SCAN-based fair dequeue
• Activity handler pattern — pluggable persistence via PostgresHandler (default) and IPCHandler (worker processes)
• Task retry with backoff — failed tasks requeue as high priority with AGENTEXEC_MAX_TASK_RETRIES (default 3)
• Kafka backend (experimental) — pip install agentexec[kafka] for queue and schedule via Kafka (state ops raise NotImplementedError)
• Typed worker IPC — TaskFailed, LogEntry, ActivityUpdated messages over multiprocessing.Queue
• Schedule composite keys — {task_name}:{cron}:{context_hash} for unique schedule identity

Improvements

• Class-based backend architecture with ABCs
• Task is pure data, TaskDefinition owns behavior
• Session management via configure_engine/get_session (Pool owns the engine)
• Status enum extracted to activity/status.py (no SQLAlchemy dependency)
• 277 tests passing across partitions, retries, execute lifecycle, schedules