feat(frontend): add Helm chart browser, monitoring, chart-references and values templates pages

Add new frontend pages for the multi-tenant OCDP platform:

- Charts page (/charts): Browse Harbor OCI registries to list Helm chart repositories
  and versions, with deploy modal to launch charts on selected clusters
- Monitoring page (/monitoring): Display cluster metrics (CPU/Memory/GPU usage)
  and per-node details with resource utilization bars
- Chart References page (/chart-references): CRUD for chart metadata references
- Values Templates page (/templates): CRUD for Helm values templates with version
  history and rollback support
- Sidebar: Add Charts navigation, update Storage and Templates links
- api.ts: Add all API client functions (clusterApi, registryApi, instanceApi,
  monitoringApi, storageApi, chartReferenceApi, valuesTemplateApi,
  workspaceApi, userApi) with full TypeScript types

Note: deploy flow and values template rollback not yet end-to-end tested.

backend/hash.go

@@ -0,0 +1,34 @@
+//go:build ignore
+
+package main
+
+import (
+	"crypto/rand"
+	"encoding/base64"
+	"fmt"
+
+	"golang.org/x/crypto/argon2"
+)
+
+func main() {
+	password := "admin123"
+
+	memory := 64 * 1024
+	iterations := 3
+	parallelism := 2
+	saltLength := 16
+	keyLength := 32
+
+	salt := make([]byte, saltLength)
+	rand.Read(salt)
+
+	hash := argon2.IDKey([]byte(password), salt, uint32(iterations), uint32(memory), uint8(parallelism), uint32(keyLength))
+
+	b64Salt := base64.RawStdEncoding.EncodeToString(salt)
+	b64Hash := base64.RawStdEncoding.EncodeToString(hash)
+
+	encodedHash := fmt.Sprintf("$argon2id$v=%d$m=%d,t=%d,p=%d$%s$%s",
+		argon2.Version, memory, iterations, parallelism, b64Salt, b64Hash)
+
+	fmt.Println(encodedHash)
+}