feat: advanced clusteraccess library (#173)

* add improved clusteraccess library

* fix bugs and enable unit test support

* add label conflict detection

* add unit tests for advanced cluster access reconciler

* enable stuff to depend on request

* make clusteraccess library use the advanced library internally

* move parameterization into own interface for simpler method signatures

* fixes and documentation

* fix typo

* review feedback

Co-authored-by: René Schünemann <rene.schuenemann@sap.com>

* create explicit types for the generator functions passed into the ClusterRegistrationBuilder constructors

* add background info about mcp architecture to documentation

---------

Co-authored-by: René Schünemann <rene.schuenemann@sap.com>

Author: Diaphteiros

docs/README.md

@@ -8,6 +8,10 @@
 - [ManagedControlPlane v2](controller/managedcontrolplane.md)
 - [Cluster Scheduler](controller/scheduler.md)
 
+## Libraries
+
+- [The ClusterAccess Library](libraries/clusteraccess.md)
+
 ## Resources
 
 - [Cluster Provider: Gardener [Resource Example]](resources/cluster-provider-gardener.md)

docs/libraries/.docnames

@@ -0,0 +1,3 @@
+{
+    "header": "Libraries"
+}

docs/libraries/clusteraccess.md

@@ -0,0 +1,12 @@
+apiVersion: clusters.openmcp.cloud/v1alpha1
+kind: Cluster
+metadata:
+  name: cluster-01
+  namespace: test
+spec:
+  profile: my-profile
+  kubernetes:
+    version: "1.32"
+  purposes:
+  - test
+  tenancy: Exclusive

lib/clusteraccess/advanced/clusteraccess.go

@@ -0,0 +1,12 @@
+apiVersion: clusters.openmcp.cloud/v1alpha1
+kind: ClusterRequest
+metadata:
+  name: cr-01
+  namespace: test
+spec:
+  purpose: test
+status:
+  phase: Granted
+  cluster:
+    name: cluster-01
+    namespace: test

lib/clusteraccess/advanced/clusteraccess_test.go

@@ -0,0 +1,6 @@
+apiVersion: clusters.openmcp.cloud/v1alpha1
+kind: AccessRequest
+metadata:
+  name: foo--ar-conflict--fb
+  namespace: afb2bcb3-2889-85f2-88a6-ea4ac5f2dd68
+spec: {}

lib/clusteraccess/advanced/testdata/test-01/cluster-01.yaml

@@ -0,0 +1,7 @@
+apiVersion: clusters.openmcp.cloud/v1alpha1
+kind: ClusterRequest
+metadata:
+  name: foo--cr-conflict--fb
+  namespace: 3d95cbf8-d468-88c6-9ca8-a3be991689a8
+spec:
+  purpose: test