fix: pin MCP sidecar versions for stability

- Pin kubernetes-mcp to v0.0.57 (Jan 27, 2025) with token exchange and field selector support
- Pin flux-mcp to v0.41.1 (already pinned)
- Pin homeassistant-mcp to v6.7.1 (Feb 20, 2026) - latest stable release
- Update documentation with version details
- Bump chart version to 0.1.19

This ensures reproducible deployments and prevents unexpected breaking changes
from floating tags (latest/stable).

Generated with Claude Code via Happy

Co-Authored-By: Claude <noreply@anthropic.com>
Co-Authored-By: Happy <yesreply@happy.engineering>

CLAUDE.md

@@ -81,11 +81,11 @@ Container start
 
 MCP (Model Context Protocol) servers run as sidecar containers in the pod, enabling AI assistants to interact with various services:
 
-| Sidecar | Image | Port | Endpoint | Default |
-|---------|-------|------|----------|---------|
-| `kubernetes-mcp` | `quay.io/containers/kubernetes_mcp_server` | 8080 | `http://localhost:8080/sse` | Enabled |
-| `flux-mcp` | `ghcr.io/controlplaneio-fluxcd/flux-operator-mcp` | 8081 | `http://localhost:8081/sse` | Enabled |
-| `homeassistant-mcp` | `ghcr.io/homeassistant-ai/ha-mcp` | 8087 | `http://localhost:8087/sse` | Disabled |
+| Sidecar | Image | Version | Port | Endpoint | Default |
+|---------|-------|---------|------|----------|---------|
+| `kubernetes-mcp` | `quay.io/containers/kubernetes_mcp_server` | v0.0.57 | 8080 | `http://localhost:8080/sse` | Enabled |
+| `flux-mcp` | `ghcr.io/controlplaneio-fluxcd/flux-operator-mcp` | v0.41.1 | 8081 | `http://localhost:8081/sse` | Enabled |
+| `homeassistant-mcp` | `ghcr.io/homeassistant-ai/ha-mcp` | v6.7.1 | 8087 | `http://localhost:8087/sse` | Disabled |
 
 **Note:**
 - Kubernetes and Flux sidecars require `clusterAccess` != `none` to be deployed (they need RBAC permissions)