feat: add self-evolution plugin — agent self-optimization system

Add a comprehensive self-evolution system that enables Hermes Agent
to continuously improve through automated analysis and optimization:

Core components:
- reflection_engine: Nightly session analysis (1:00 AM)
- evolution_proposer: Generate improvement proposals from insights
- quality_scorer: Multi-dimensional session quality evaluation
- strategy_injector: Inject learned strategies into new sessions
- strategy_compressor: Strategy optimization and deduplication
- git_analyzer: Code change pattern analysis
- rule_engine: Pattern-based rule generation
- feishu_notifier: Feishu card notifications for evolution events

Storage:
- db.py: SQLite telemetry storage
- strategy_store: Persistent strategy storage
- models.py: Data models

Plugin integration:
- plugin.yaml, hooks.py, __init__.py for plugin system
- cron_jobs.py for scheduled tasks

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

self_evolution/plugin.yaml

@@ -0,0 +1,7 @@
+name: self_evolution
+version: "1.0.0"
+description: "Agent self-optimization and continuous evolution — dream consolidation at 1:00, Feishu approval at 19:00"
+provides_hooks:
+  - post_tool_call
+  - on_session_end
+  - pre_llm_call