add gh and postman links to docs (#3121)

docs/apis-tools/console-api-reference.md

@@ -8,6 +8,10 @@ The Camunda 8 management API provides a programmatic interface for managing Camu
 
 A detailed API description can be found [here](https://console.cloud.camunda.io/customer-api/openapi/docs/#/) via Swagger. With a valid access token, this offers an interactive API experience against your Camunda 8 cluster.
 
+:::note
+You can also work with this API in our [Postman collection](https://www.postman.com/camundateam/workspace/camunda-8-postman/collection/20317927-4c378140-b9ca-4f2d-b4d5-479ab0fcc472?action=share&creator=11465105), or check it out in [GitHub](https://github.com/camunda-community-hub/camunda-8-api-postman-collection).
+:::
+
 ## Authentication
 
 To access the API endpoint, you need an access token. Your client must send a header in each request:

docs/apis-tools/grpc.md

@@ -9,6 +9,10 @@ keywords: ["backpressure", "back-pressure", "back pressure"]
 
 To authorize the Zeebe API (gRPC) in a [Self-Managed](/self-managed/about-self-managed.md) setup, see [client authorization](/self-managed/zeebe-deployment/security/client-authorization.md).
 
+:::note
+Work with this API in our [Postman collection](https://www.postman.com/camundateam/workspace/camunda-8-postman/collection/24684262-73d9bf8a-b29f-46c1-93fd-5c4825b10bf4?action=share&creator=11465105).
+:::
+
 ## Gateway service
 
 The Zeebe client gRPC API is exposed through a single gateway service. The current version of the protocol buffer file can be found in the [Zeebe repository](https://github.com/camunda/zeebe/blob/main/gateway-protocol/src/main/proto/gateway.proto).

docs/apis-tools/operate-api/overview.md

@@ -10,6 +10,10 @@ Requests and responses are in JSON notation. Some objects have additional endpoi
 For example, `process-definitions` has an endpoint to get the process-definition as XML representation.
 In case of errors, Operate API returns an error object.
 
+:::note
+Work with this API in our [Postman collection](https://www.postman.com/camundateam/workspace/camunda-8-postman/collection/20317927-9d9314a2-4cff-40ab-90ea-98e28ca1f81c?action=share&creator=11465105), and check it out in [GitHub](https://github.com/camunda-community-hub/camunda-8-api-postman-collection).
+:::
+
 ## API documentation as Swagger
 
 A detailed API description is also available as Swagger UI at `https://${base-url}/swagger-ui/index.html`.

docs/apis-tools/tasklist-api-rest/tasklist-api-rest-overview.md

@@ -24,6 +24,10 @@ For SaaS: `https://${REGION}.tasklist.camunda.io:443/${CLUSTER_ID}/swagger-ui/in
 Find your region and cluster id under connection information in your client credentials.
 :::
 
+## API in Postman
+
+Work with this API in our [Postman collection](https://www.postman.com/camundateam/workspace/camunda-8-postman/collection/26079299-f0db0193-0557-4acd-8e94-ecdaeffbaa5d?action=share&creator=11465105), and check it out in [GitHub](https://github.com/camunda-community-hub/camunda-8-api-postman-collection).
+
 ## Endpoints
 
 | Endpoint (HTTP verb + URL path)                                                                                                                                 |                                                                       Description |

docs/apis-tools/tasklist-api/tasklist-api-overview.md

@@ -24,7 +24,9 @@ For SaaS: `https://${REGION}.tasklist.camunda.io:443/${CLUSTER_ID}/graphql`, and
 
 ## Obtaining the Tasklist schema
 
-To obtain the Tasklist GraphQL schema, send a request to the endpoint with a GraphQL introspection query as described [here](https://graphql.org/learn/introspection/), or use the [generated API documentation](/docs/apis-tools/tasklist-api/generated.md).
+To obtain the Tasklist GraphQL schema, check out the API collection in [GitHub](https://github.com/camunda-community-hub/camunda-8-api-postman-collection), which is fully functioning in [Postman](https://www.postman.com/camundateam/workspace/camunda-8-postman/collection/20317927-6394943f-b57c-4c04-acf9-391a8614103b?action=share&creator=11465105).
+
+Alternatively, send a request to the endpoint with a GraphQL introspection query as described [here](https://graphql.org/learn/introspection/), or use the [generated API documentation](/docs/apis-tools/tasklist-api/generated.md).
 
 There are also several [tools to explore GraphQL APIs](https://altair.sirmuel.design).
 

docs/apis-tools/web-modeler-api/index.md

@@ -18,6 +18,10 @@ A detailed API description is available as [OpenAPI](https://www.openapis.org/)
 for SaaS and at [http://localhost:8070/swagger-ui.html](http://localhost:8070/swagger-ui.html) for Self-Managed
 installations.
 
+## API in Postman
+
+Work with this API in our [Postman collection](https://www.postman.com/camundateam/workspace/camunda-8-postman/collection/26079299-0bb668f4-af6a-4ab0-88a3-c78b900125ed?action=share&creator=11465105).
+
 ## Limitations
 
 When using Web Modeler API:

optimize/apis-tools/optimize-api/optimize-api-authentication.md

@@ -17,7 +17,7 @@ The token used to access the Optimize API can be a configurable shared secret (e
 
 Refer to [Public API Configuration](../../self-managed/optimize-deployment/configuration/system-configuration.md#public-api) for the particular configuration to access the public API using a token.
 
-### How to obtain the access token for Camunda 8
+## How to obtain the access token for Camunda 8
 
 You must obtain a token to use the Optimize API. When you create an Optimize [client]($docs$/guides/setup-client-connection-credentials/), you get all the information needed to connect to Optimize.
 
@@ -59,3 +59,7 @@ If the authentication is successful, the authentication server sends back the ac
   "token_type": "Bearer"
 }
 ```
+
+## Use it in Postman
+
+Work with this API in our [Postman collection](https://www.postman.com/camundateam/workspace/camunda-8-postman/collection/20317927-9d9314a2-4cff-40ab-90ea-98e28ca1f81c?action=share&creator=11465105).