[docs] Improve connection between library references and their APIs (#22800)

Signed-off-by: Max Pumperla <max.pumperla@googlemail.com>

doc/source/_toc.yml

@@ -17,6 +17,7 @@ parts:
           - file: data/user-guide
           - file: data/key-concepts
           - file: data/examples/big_data_ingestion
+          - file: data/package-ref
 
       - file: train/train
         title: Ray Train
@@ -27,6 +28,8 @@ parts:
           - file: train/migration-guide
           - file: raysgd/raysgd
             title: "RaySGD v1: Distributed Training Wrappers"
+          - file: train/api
+
       - file: tune/index
         title: Ray Tune
         sections:
@@ -57,6 +60,7 @@ parts:
           - file: tune/examples/index
           - file: tune/faq
           - file: tune/api_docs/overview.rst
+
       - file: serve/index
         title: Ray Serve
         sections:
@@ -70,6 +74,8 @@ parts:
           - file: serve/architecture
           - file: serve/tutorials/index
           - file: serve/faq
+          - file: serve/package-ref
+
       - file: rllib/index
         title: Ray RLlib
         sections:
@@ -85,6 +91,8 @@ parts:
               - file: rllib/rllib-offline
               - file: rllib/rllib-dev
           - file: rllib/rllib-examples
+          - file: rllib/package_ref/index
+
       - file: workflows/concepts
         title: Ray Workflows
         sections:
@@ -95,6 +103,7 @@ parts:
           - file: workflows/events
           - file: workflows/comparison
           - file: workflows/advanced
+          - file: workflows/package-ref
       - file: ray-more-libs/index
         title: More Ray ML Libraries
 
@@ -122,6 +131,7 @@ parts:
           - file: ray-core/examples/using-ray-with-pytorch-lightning
           - file: ray-core/examples/dask_xgboost/dask_xgboost
           - file: ray-core/examples/modin_xgboost/modin_xgboost
+      - file: ray-core/package-ref
 
   - caption: Ray Clusters
     chapters:
@@ -129,6 +139,7 @@ parts:
       - file: cluster/user-guide
       - file: cluster/cloud
       - file: cluster/deploy
+      - file: cluster/api
 
   - caption: References
     chapters:

doc/source/cluster/api.rst

@@ -0,0 +1,9 @@
+Ray Cluster API
+===============
+
+.. toctree::
+    :maxdepth: 2
+    :caption: Ray Cluster API References
+
+    ../cluster/reference.rst
+    ../cluster/jobs-package-ref.rst