feat(memory): modernize symbolic + pool_processor, wire post-rollover chain
- Modernize symbolic.py module: seedgo introspection gate, aipass.memory imports
- Modernize 6 symbolic handlers: remove MEMORY_BANK paths, use _MEMORY_ROOT
- Modernize pool_processor.py: fix config path (memory_json → config), add memory_pool config section
- Wire post-rollover chain in orchestrator.py: Trigger.fire('rollover_complete'), central_writer, dashboard_push, pool_processor
- Expose check_and_rollover() via modules/rollover.py for cross-branch access
- Update pyrightconfig.json with memory venv site-packages path
FPLAN-0054, FPLAN-0062
Co-Authored-By: @memory <memory@aipass>
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>