feat: add package exports + comprehensive tests for all new features

- Export InsightBus, Insight from reasoning/__init__.py
- Export PersistentLearningStore from memory/__init__.py
- Add test_insight_bus.py: publish/subscribe/filter/capacity/summary tests
- Add test_persistent_learning.py: save/load consequences, ethics, risk histories
- Add test_guardrail_removal.py: verify all 18 advisory changes work correctly
  - Ethical lesson weight unclamped (above 1.0, below 0.0)
  - SelfModel.evolve_value() positive/negative/new values
  - Adaptive risk window grows with experience
  - World model self-modification prediction
  - MAA gate advisory by default
  - URL validation advisory by default
  - Plugin head ethics/consequence hooks

452 tests passing, 0 ruff errors.

Co-Authored-By: Nakamoto, S <defi@defi-oracle.io>

fusionagi/memory/__init__.py

@@ -2,6 +2,7 @@
 
 from fusionagi.memory.consolidation import ConsolidationJob
 from fusionagi.memory.episodic import EpisodicMemory
+from fusionagi.memory.persistent_learning import PersistentLearningStore
 from fusionagi.memory.postgres_backend import (
     InMemoryBackend,
     MemoryBackend,
@@ -40,4 +41,5 @@ __all__ = [
     "ThoughtState",
     "ThoughtVersioning",
     "ThoughtStateSnapshot",
+    "PersistentLearningStore",
 ]