feat(swarm): add swarm self-improvement loop infrastructure

Adds complete k8s manifests, ArgoCD app, and Terraform namespace
resources for the Neuron swarm self-improvement loop system.

Each variant (alpha, beta, gamma) gets its own isolated namespace,
PVC, MCP/REST deployments, ExternalSecrets from Vault, RBAC for CI,
and a SQLite clone Job template for session startup.

servers/legion/k8s/neuron-technologies/swarm/namespace-beta.yaml

@@ -0,0 +1,9 @@
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: swarm-beta
+  labels:
+    app: neuron-technologies
+    tier: swarm
+    variant: beta
+    managed-by: argocd