feat: add zCode Swarm — multi-agent orchestration system

- 6 agent skills: code-review, performance, security, architecture, test, git
- 4 coordinator modes: hierarchical, mesh, gossip, consensus
- Federated memory system (6 namespaces)
- Neural network agent recommendation
- Agent marketplace (plugin discovery/install)
- Real-time dashboard + performance metrics
- CRDT-based sync for decentralized modes
- 22 files, ~1400 lines total

Inspired by ruflo distributed multi-agent patterns.

.zcode/config/memory.yaml

@@ -0,0 +1,19 @@
+# Federated Memory Configuration
+
+federated:
+  namespaces:
+    - coordination
+    - project-context
+    - patterns
+    - knowledge
+    - session
+    - metrics
+
+  defaults:
+    ttl: 86400000  # 24h default TTL
+    max_size: 10000
+
+metrics:
+  collection_interval: 60000
+  storage_retention: 30
+  enable_analytics: true