Prepare azure.ai.agents 0.1.28-preview patch release (#7941)

* Initial plan

* chore: prepare azure.ai.agents 0.1.28-preview release

Agent-Logs-Url: https://github.com/Azure/azure-dev/sessions/870af740-8731-4cff-be35-f8763b083afb

Co-authored-by: trangevi <26490000+trangevi@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: trangevi <26490000+trangevi@users.noreply.github.com>

Author: Copilot

cli/azd/extensions/azure.ai.agents/CHANGELOG.md

@@ -1,5 +1,9 @@
 # Release History
 
+## 0.1.28-preview (2026-04-28)
+
+- [[#7930]](https://github.com/Azure/azure-dev/pull/7930) Fetch the hosted-agent supported regions list at runtime from a remote JSON manifest with an embedded fallback, replacing the hardcoded list; region data can now be updated without cutting an extension release.
+
 ## 0.1.27-preview (2026-04-22)
 
 - [[#7880]](https://github.com/Azure/azure-dev/pull/7880) Remove ACR endpoint pre-check from the package step; packaging no longer fails early when `AZURE_CONTAINER_REGISTRY_ENDPOINT` is absent, allowing provisioning to create the registry first for new projects.

cli/azd/extensions/azure.ai.agents/extension.yaml

@@ -5,7 +5,7 @@ displayName: Foundry agents (Preview)
 description: Ship agents with Microsoft Foundry from your terminal. (Preview)
 usage: azd ai agent <command> [options]
 # NOTE: Make sure version.txt is in sync with this version.
-version: 0.1.27-preview
+version: 0.1.28-preview
 requiredAzdVersion: ">1.23.13"
 language: go
 capabilities:

cli/azd/extensions/azure.ai.agents/version.txt

@@ -1 +1 @@
-0.1.27-preview
+0.1.28-preview