openapi: Improve Bots documentation by dividing bots.

Firstly divide the Bot schema into Bot and BasicBot for ease
of reusability. Also separate bot remove and bot delete into
two separate events.

zerver/openapi/zulip.yaml

@@ -2581,18 +2581,13 @@ paths:
                                   enum:
                                     - update
                                 bot:
-                                  type: object
-                                  description: |
+                                  allOf:
+                                    - description: |
                                         Object containing details about the changed bot.
                                         It contains two properties: the user id of the bot and
                                         the property to be changed. The changed property is one
-                                    of the properties of bot which can be seen in the `bot`
-                                    `add` event.
-                                  properties:
-                                    user_id:
-                                      type: integer
-                                      description: |
-                                        The user ID of the modified bot.
+                                        of the remaining properties listed below.
+                                    - $ref: "#/components/schemas/BasicBot"
                               example:
                                 {
                                   "type": "realm_bot",
@@ -2626,7 +2621,6 @@ paths:
                                   type: string
                                   enum:
                                     - remove
-                                    - delete
                                 bot:
                                   type: object
                                   description: |
@@ -2648,6 +2642,40 @@ paths:
                                     {"user_id": 35, "full_name": "Foo Bot"},
                                   "id": 1,
                                 }
+                            - type: object
+                              additionalProperties: false
+                              description: |
+                                Event sent to all users when a bot has been deactivated.
+                                Note that this is very similar to the bot_remove event
+                                and one of them will be removed soon.
+                              properties:
+                                id:
+                                  type: integer
+                                type:
+                                  type: string
+                                  enum:
+                                    - realm_bot
+                                op:
+                                  type: string
+                                  enum:
+                                    - delete
+                                bot:
+                                  type: object
+                                  description: |
+                                    Object containing details about the deactivated bot.
+                                  properties:
+                                    user_id:
+                                      type: integer
+                                      description: |
+                                        The user ID of the deactivated bot.
+                              example:
+                                {
+                                  "type": "realm_bot",
+                                  "op": "delete",
+                                  "bot":
+                                    {"user_id": 35, "full_name": "Foo Bot"},
+                                  "id": 1,
+                                }
                             - type: object
                               additionalProperties: false
                               description: |
@@ -8271,16 +8299,10 @@ components:
 
             **Changes**: Deprecated in Zulip 3.0 (feature level 1), use
             `stream_post_policy` instead.
-    Bot:
+    BasicBot:
       type: object
       additionalProperties: false
-      description: |
-        Object containing details of a bot.
       properties:
-        email:
-          type: string
-          description: |
-            The email of the bot.
         user_id:
           type: integer
           description: |
@@ -8289,19 +8311,6 @@ components:
           type: string
           description: |
             The full name of the bot.
-        bot_type:
-          type: integer
-          nullable: true
-          description: |
-            An integer describing the type of bot:
-            * `1` for a `Generic` bot.
-            * `2` for an `Incoming webhook` bot.
-            * `3` for an `Outgoing webhook` bot.
-            * `4` for an `Embedded` bot.
-        is_active:
-          type: boolean
-          description: |
-            A boolean describing whether the user account has been deactivated.
         api_key:
           type: string
           description: |
@@ -8379,6 +8388,29 @@ components:
                       The name of the bot.
                   config_data:
                     $ref: "#/components/schemas/Config"
+    Bot:
+      allOf:
+        - $ref: "#/components/schemas/BasicBot"
+        - description: |
+            Object containing details of a bot.
+        - properties:
+            email:
+              type: string
+              description: |
+                The email of the bot.
+            bot_type:
+              type: integer
+              nullable: true
+              description: |
+                An integer describing the type of bot:
+                * `1` for a `Generic` bot.
+                * `2` for an `Incoming webhook` bot.
+                * `3` for an `Outgoing webhook` bot.
+                * `4` for an `Embedded` bot.
+            is_active:
+              type: boolean
+              description: |
+                A boolean describing whether the user account has been deactivated.
     Config:
       type: object
       description: |