Unified storage: Add quotas app to apiserver (#114425)

* initial generation

* went through doc to add new resource

* added dummy kind so grafana will run

* added dummy handler and custom route

* fix app name

* gets custom route working - still a dummy route

* adds groupOverride to manifest

* adds quotas to grpc client and server

* WIP - trying to get api recognized - not working

* Gets route working

* fixes group and resource vars

* expects group and resource as separate params

* set content-type header on response

* removes Quotas kind and regens

* Update grafana-app-sdk to v0.48.5

* Update codegen

* updates manifest

* formatting

* updates grafana-app-sdk version to 0.48.5

* regen ResourceClient mocks

* adds tests

* remove commented code

* uncomment go mod tidy

* fix tests and make update workspace

* adds quotas app to codeowners

* formatting

* make gen-apps

* deletes temp file

* fix generated folder code

* make gofmt

* make gen-go

* make update-workspace

* add COPY apps/quotas to Dockerfile

* fix test mock

* fixes undefined NewFolderStatus()

* make gen-apps, and add func for NewFolderStatus

* make gen-apps again

* make update-workspace

* regen folder_object_gen.go

* gofmt

* fix linting

* apps/folder make update-workspace

* make gen-apps

* make gen-apps

* fixes enterprise_imports.go

* go get testcontainers

* adds feature toggle

* make update-workspace

* fix go mod

* fix another client mock

---------

Co-authored-by: Steve Simpson <steve@grafana.com>

pkg/storage/unified/proto/resource.proto

@@ -587,6 +587,22 @@ message ResourceTableRow {
   bytes object = 4;
 }
 
+message QuotaUsageRequest {
+  // Namespace (tenant)
+  ResourceKey key = 1;
+}
+
+message QuotaUsageResponse {
+  // Error details
+  ErrorResult error = 1;
+
+  // Current usage
+  int64 usage = 2;
+
+  // Current limit
+  int64 limit = 3;
+}
+
 // This provides the CRUD+List+Watch support needed for a k8s apiserver
 // The semantics and behaviors of this service are constrained by kubernetes
 // This does not understand the resource schemas, only deals with json bytes
@@ -631,3 +647,8 @@ service Diagnostics {
   // Check if the service is healthy
   rpc IsHealthy(HealthCheckRequest) returns (HealthCheckResponse);
 }
+
+service Quotas {
+  // Get current quota usage and limits
+  rpc GetQuotaUsage(QuotaUsageRequest) returns (QuotaUsageResponse);
+}