[ResponseOps][Rules] OAS schema registration for newly versioned Rule APIs (#189153)

## Summary

Issue:  https://github.com/elastic/kibana/issues/187574

This PR updates `request` and `response` schemas below for rule APIs to
generate OAS documentation:
- `POST /api/alerting/rule/{id?}/_enable`
- `POST /api/alerting/rule/{id?}/_disable`
- `POST /api/alerting/rule/{id?}/_update_api_key`


### How to test

1. Start ES
2. Add `server.oas.enabled: true` to `kibana.dev.yml`
3. Start Kibana `yarn start --no-base-path`
4. `curl -s -u elastic:changeme
http://localhost:5601/api/oas\?pathStartsWith\=/api/alerting/rule/ | jq`
5. Look for `_enable`, `_disable` and `_update_api_key` in the resulting
JSON

x-pack/plugins/alerting/common/routes/rule/apis/disable/schemas/v1.ts

@@ -10,11 +10,22 @@ import { schema } from '@kbn/config-schema';
 export const disableRuleRequestBodySchema = schema.nullable(
   schema.maybe(
     schema.object({
-      untrack: schema.maybe(schema.boolean({ defaultValue: false })),
+      untrack: schema.maybe(
+        schema.boolean({
+          defaultValue: false,
+          meta: {
+            description: "Defines whether this rule's alerts should be untracked.",
+          },
+        })
+      ),
     })
   )
 );
 
 export const disableRuleRequestParamsSchema = schema.object({
-  id: schema.string(),
+  id: schema.string({
+    meta: {
+      description: 'The identifier for the rule.',
+    },
+  }),
 });

x-pack/plugins/alerting/common/routes/rule/apis/enable/schemas/v1.ts

@@ -8,5 +8,9 @@
 import { schema } from '@kbn/config-schema';
 
 export const enableRuleRequestParamsSchema = schema.object({
-  id: schema.string(),
+  id: schema.string({
+    meta: {
+      description: 'The identifier for the rule.',
+    },
+  }),
 });

x-pack/plugins/alerting/common/routes/rule/apis/update_api_key/schemas/v1.ts

@@ -8,5 +8,9 @@
 import { schema } from '@kbn/config-schema';
 
 export const updateApiKeyParamsSchema = schema.object({
-  id: schema.string(),
+  id: schema.string({
+    meta: {
+      description: 'The identifier for the rule.',
+    },
+  }),
 });

x-pack/plugins/alerting/server/routes/index.ts

@@ -19,7 +19,7 @@ import { updateRuleRoute } from './rule/apis/update/update_rule_route';
 import { deleteRuleRoute } from './rule/apis/delete/delete_rule_route';
 import { aggregateRulesRoute } from './rule/apis/aggregate/aggregate_rules_route';
 import { disableRuleRoute } from './rule/apis/disable/disable_rule_route';
-import { enableRuleRoute } from './rule/apis/enable/enable_rule';
+import { enableRuleRoute } from './rule/apis/enable/enable_rule_route';
 import { findRulesRoute, findInternalRulesRoute } from './rule/apis/find/find_rules_route';
 import { getRuleAlertSummaryRoute } from './get_rule_alert_summary';
 import { getRuleExecutionLogRoute } from './get_rule_execution_log';

x-pack/plugins/alerting/server/routes/rule/apis/disable/disable_rule_route.ts

@@ -28,8 +28,15 @@ export const disableRuleRoute = (
         summary: 'Disable a rule',
       },
       validate: {
-        params: disableRuleRequestParamsSchemaV1,
-        body: disableRuleRequestBodySchemaV1,
+        request: {
+          params: disableRuleRequestParamsSchemaV1,
+          body: disableRuleRequestBodySchemaV1,
+        },
+        response: {
+          204: {
+            description: 'Indicates a successful call.',
+          },
+        },
       },
     },
     router.handleLegacyErrors(

x-pack/plugins/alerting/server/routes/rule/apis/enable/enable_rule_route.test.ts

@@ -5,7 +5,7 @@
  * 2.0.
  */
 
-import { enableRuleRoute } from './enable_rule';
+import { enableRuleRoute } from './enable_rule_route';
 import { httpServiceMock } from '@kbn/core/server/mocks';
 import { licenseStateMock } from '../../../../lib/license_state.mock';
 import { mockHandlerArguments } from '../../../_mock_handler_arguments';

x-pack/plugins/alerting/server/routes/rule/apis/enable/enable_rule_route.ts

@@ -27,7 +27,14 @@ export const enableRuleRoute = (
         summary: 'Enable a rule',
       },
       validate: {
-        params: enableRuleRequestParamsSchemaV1,
+        request: {
+          params: enableRuleRequestParamsSchemaV1,
+        },
+        response: {
+          204: {
+            description: 'Indicates a successful call.',
+          },
+        },
       },
     },
     router.handleLegacyErrors(

x-pack/plugins/alerting/server/routes/rule/apis/update_api_key/update_rule_api_key_route.ts

@@ -26,7 +26,14 @@ export const updateRuleApiKeyRoute = (
         summary: 'Update the API key for a rule',
       },
       validate: {
-        params: updateApiKeyParamsSchemaV1,
+        request: {
+          params: updateApiKeyParamsSchemaV1,
+        },
+        response: {
+          204: {
+            description: 'Indicates a successful call.',
+          },
+        },
       },
     },
     router.handleLegacyErrors(