feat: complete E2E deployment flow with storage layered config and values template versioning

- Instance deployment: charts browser, deploy modal, instances list
- Values Template version management (create/history/rollback)
- Storage layered config (cluster > workspace > shared priority)
- Cluster credential decryptIfNeeded for mixed encrypted/plaintext kubeconfig
- YAML syntax validation (client-side + server-side warning)
- Frontend: charts, instances, storage, templates, admin pages
- Backend: storage service, instance service, cluster service, helm client
- Multi-Tenant Kubeconfig.md: added by user

backend/scripts/init-db.sql

@@ -142,6 +142,8 @@ CREATE INDEX IF NOT EXISTS idx_workspaces_name ON workspaces(name);
 CREATE TABLE IF NOT EXISTS storage_backends (
     id VARCHAR(36) PRIMARY KEY,
     workspace_id VARCHAR(36),
+    owner_id VARCHAR(36),
+    cluster_id VARCHAR(36),
     name VARCHAR(255) NOT NULL,
     type VARCHAR(50) NOT NULL,
     config JSONB NOT NULL,
@@ -154,6 +156,8 @@ CREATE TABLE IF NOT EXISTS storage_backends (
 );
 
 CREATE INDEX IF NOT EXISTS idx_storage_workspace ON storage_backends(workspace_id);
+CREATE INDEX IF NOT EXISTS idx_storage_cluster ON storage_backends(cluster_id);
+CREATE INDEX IF NOT EXISTS idx_storage_default_cluster ON storage_backends(cluster_id, is_default) WHERE cluster_id IS NOT NULL;
 
 -- ===== Chart References 表 =====
 CREATE TABLE IF NOT EXISTS chart_references (
@@ -183,7 +187,7 @@ CREATE TABLE IF NOT EXISTS values_templates (
     is_default BOOLEAN DEFAULT FALSE,
     created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
     updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
-    UNIQUE(workspace_id, chart_reference_id, name)
+    UNIQUE(workspace_id, chart_reference_id, name, version)
 );
 
 CREATE INDEX IF NOT EXISTS idx_values_template_chart ON values_templates(chart_reference_id);