Worker Heartbeat: Use Worker Grouping instead of Runtime for Key in nexus TQ (#637)

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<!-- Describe what has changed in this PR -->
**What changed?**
use `worker_grouping_key` instead of `runtime_key` for worker command
nexus task queue


<!-- Tell your future self why have you made these changes -->
**Why?**
There can be multiple clients (i.e. with different auths) within the
same runtime/namespace, so we want a more specific category for these
nexus worker command requests


<!-- Are there any breaking changes on binary or code level? -->
**Breaking changes**
No, WIP feature


<!-- If this breaks the Server, please provide the Server PR to merge
right after this PR was merged. -->
**Server PR**

Author: yuandrew

buf.yaml

@@ -13,6 +13,8 @@ breaking:
     - WIRE_JSON
   ignore:
     - google
+    # TODO (yuandrew): remove this. Added for "heartbeat" changes
+    - temporal/api/worker/v1/message.proto
 lint:
   use:
     - DEFAULT

openapi/openapiv2.json

@@ -16307,13 +16307,13 @@
           "type": "string",
           "description": "Worker host identifier."
         },
-        "processKey": {
+        "workerGroupingKey": {
           "type": "string",
-          "title": "Worker process identifier. This id should be unique for all _processes_\nrunning workers in the namespace, and should be shared by all workers\nin the same process.\nThis will be used to build the worker command nexus task queue name:\n\"temporal-sys/worker-commands/{process_key}\""
+          "title": "Worker grouping identifier. A key to group workers that share the same client+namespace+process.\nThis will be used to build the worker command nexus task queue name:\n\"temporal-sys/worker-commands/{worker_grouping_key}\""
         },
         "processId": {
           "type": "string",
-          "description": "Worker process identifier. Unlike process_key, this id only needs to be unique\nwithin one host (so using e.g. a unix pid would be appropriate)."
+          "description": "Worker process identifier. This id only needs to be unique\nwithin one host (so using e.g. a unix pid would be appropriate)."
         },
         "currentHostCpuUsage": {
           "type": "number",

openapi/openapiv3.yaml

@@ -13648,18 +13648,16 @@ components:
         hostName:
           type: string
           description: Worker host identifier.
-        processKey:
+        workerGroupingKey:
           type: string
           description: |-
-            Worker process identifier. This id should be unique for all _processes_
-             running workers in the namespace, and should be shared by all workers
-             in the same process.
+            Worker grouping identifier. A key to group workers that share the same client+namespace+process.
              This will be used to build the worker command nexus task queue name:
-             "temporal-sys/worker-commands/{process_key}"
+             "temporal-sys/worker-commands/{worker_grouping_key}"
         processId:
           type: string
           description: |-
-            Worker process identifier. Unlike process_key, this id only needs to be unique
+            Worker process identifier. This id only needs to be unique
              within one host (so using e.g. a unix pid would be appropriate).
         currentHostCpuUsage:
           type: number

temporal/api/worker/v1/message.proto

@@ -54,15 +54,12 @@ message WorkerHostInfo {
   // Worker host identifier.
   string host_name = 1;
 
-
-  // Worker process identifier. This id should be unique for all _processes_
-  // running workers in the namespace, and should be shared by all workers
-  // in the same process.
+  // Worker grouping identifier. A key to group workers that share the same client+namespace+process.
   // This will be used to build the worker command nexus task queue name:
-  // "temporal-sys/worker-commands/{process_key}"
-  string process_key = 5;
+  // "temporal-sys/worker-commands/{worker_grouping_key}"
+  string worker_grouping_key = 5;
 
-  // Worker process identifier. Unlike process_key, this id only needs to be unique
+  // Worker process identifier. This id only needs to be unique
   // within one host (so using e.g. a unix pid would be appropriate).
   string process_id = 2;