[ruby/prism] Add document CallOrWriteNode fields

Partially: https://github.com/ruby/prism/issues/2123

https://github.com/ruby/prism/commit/3c01cc7c77

prism/config.yml

@@ -1555,19 +1555,54 @@ nodes:
       - name: receiver
         type: node?
         kind: non-void expression
+        comment: |
+          The object that the method is being called on. This can be either `nil` or any [non-void expressions](https://github.com/ruby/prism/blob/main/docs/parsing_rules.md#non-void-expression).
+
+              foo.bar ||= value
+              ^^^
       - name: call_operator_loc
         type: location?
+        comment: |
+          Represents the location of the call operator.
+
+              foo.bar ||= value
+                 ^
       - name: message_loc
         type: location?
+        comment: |
+          Represents the location of the message.
+
+              foo.bar ||= value
+                  ^^^
       - name: read_name
         type: constant
+        comment: |
+          Represents the name of the method being called.
+
+              foo.bar ||= value # read_name `:bar`
+                  ^^^
       - name: write_name
         type: constant
+        comment: |
+          Represents the name of the method being written to.
+
+              foo.bar ||= value # write_name `:bar=`
+                  ^^^
       - name: operator_loc
         type: location
+        comment: |
+          Represents the location of the operator.
+
+              foo.bar ||= value
+                      ^^^
       - name: value
         type: node
         kind: non-void expression
+        comment: |
+          Represents the value being assigned.
+
+              foo.bar ||= value
+                          ^^^^^
     comment: |
       Represents the use of the `||=` operator on a call.