fix(docs): Change V2 Inference Protocol to OIP (#5297)

* Change from V2 protocol to OIP

* Add back endpoint categories for clarity

* Grammar

* Add model inference under endpoints

Author: paulb-seldon

doc/source/reference/apis/v2-protocol.md

@@ -1,18 +1,17 @@
-# V2 Inference Protocol
+# Open Inference Protocol
 
-The V2 Inference Protocol is an industry-wide effort to provide an standardised
+The Open Inference Protocol is an industry-wide effort to provide a standardized
 protocol to communicate with different inference servers (e.g. MLServer,
 Triton, etc.) and orchestrating frameworks (e.g. Seldon Core, KServe, etc.).
-The spec of the V2 Inference Protocol defines both the endpoints and payload
+The spec of the Open Inference Protocol defines both the endpoints and payload
 schemas for REST and gRPC interfaces.
 
-As part of the V2 Protocol definition, you can find dedicated endpoints for:
+As part of the Open Inference Protocol definition, you can find dedicated endpoints for:
 
-- Health endpoints, to assess liveness and readiness of your model.
-- Inference endpoints, to interact with your model.
-- Metadata endpoints, to query your model metadata (e.g. expected inputs, expected
+- Model controls: Call model inference, interact with your model, and load and unload models dynamically
+- Health: Assess liveness and readiness of your model.
+- Metadata: Query your model metadata (e.g. expected inputs, expected
   outputs, etc.).
-- Model repository endpoints, to load and unload models dynamically.
 
 
 ## REST