Add core service infrastructure

- NATS event bus (pub/sub, JetStream, KV storage)
- Service registry with health monitoring
- Base service class with lifecycle management
- Config system
- Logger with Vi formatting

Adapted from Lyra's patterns, namespace changed to vi.*

🦊💕

.gitignore

@@ -0,0 +1,30 @@
+# Python
+__pycache__/
+*.py[cod]
+*$py.class
+*.so
+.Python
+.venv/
+venv/
+ENV/
+
+# Logs
+logs/
+*.log
+
+# Data
+data/
+
+# IDE
+.idea/
+.vscode/
+*.swp
+*.swo
+
+# OS
+.DS_Store
+Thumbs.db
+
+# Secrets
+*.env
+!.env.example