doc: Update description on module load/open (#994)

## Problem

## Solution

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## License

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under the terms of the Apache 2.0 license.

Signed-off-by: nkomonen-amazon <[email protected]>

Author: nkomonen-amazon

telemetry/definitions/commonDefinitions.json

@@ -7136,7 +7136,7 @@
         },
         {
             "name": "toolkit_didLoadModule",
-            "description": "The module has loaded, i.e it has rendered/resolved/finished. Use this after `toolkit_willOpenModule` to indicate success.",
+            "description": "The module has loaded, i.e it has rendered/resolved/finished. You can use this metric by itself, OR after `toolkit_willOpenModule` + `traceId` to close the loop on an asynchronous operation.",
             "metadata": [
                 {
                     "type": "attempts",
@@ -7338,7 +7338,7 @@
         },
         {
             "name": "toolkit_willOpenModule",
-            "description": "The opening of a module **started**. This does not imply it successfully finished, use `toolkit_didLoadModule` for that. The open/load separation exists because it may be difficult to capture then entire process in a single metric. A 'module' is a general term that represents things like: a view, feature, resource, ... ",
+            "description": "Indicates a module opening attempt began, not its successful completion. For load confirmation, use `toolkit_didLoadModule` with matching `traceId`. This separation handles asynchronous processes that can't be captured in a single metric. 'Module' refers to components like views, features, resources, etc.",
             "metadata": [
                 {
                     "type": "module",