[Container Apps] Fix Azure/azure-cli-extensions#10018: Fix invalid API version by using valid preview clients consistently

[Copilot]

The extension inconsistently fell back to the core module's ManagedEnvironmentClient and ContainerAppClient in several code paths. These core clients use CURRENT_API_VERSION = "2025-01-01" which is unavailable in some regions/subscriptions, causing InvalidApiVersionParameter errors. The extension already defines ManagedEnvironmentPreviewClient and ContainerAppPreviewClient with a valid API version (2025-10-02-preview) — they just weren't used uniformly.

Changes

• _clients.py: Added CURRENT_API_VERSION = "2025-07-01" (latest stable Microsoft.App version) as an extension-level constant.
• containerapp_decorator.py, containerapp_job_decorator.py: get_environment_client() fallback path (no env / no env-type specified) now returns ManagedEnvironmentPreviewClient instead of the core ManagedEnvironmentClient. Removed unused imports.
• containerapp_sessionpool_decorator.py: Switched import from azure.cli.command_modules.containerapp._clients.ManagedEnvironmentClient to the extension's ManagedEnvironmentPreviewClient.
• _dev_service_utils.py: DevServiceUtils.create_service and delete_service now use ManagedEnvironmentPreviewClient / ContainerAppPreviewClient.
• _utils.py: get_min_replicas_from_revision and get_random_replica now use ContainerAppPreviewClient instead of the core ContainerAppClient.

Related command

az containerapp, az containerapp job, az containerapp sessionpool, az containerapp add-on

General Guidelines

• Have you run azdev style <YOUR_EXT> locally? (pip install azdev required)
• Have you run python scripts/ci/test_index.py -q locally? (azdev required; see .azure-pipelines/templates/azdev_setup.yml for the install command until azdev==0.2.11b1 is on PyPI)
• My extension version conforms to the Extension version schema

For new extensions:

• My extension description/summary conforms to the Extension Summary Guidelines.

About Extension Publish

There is a pipeline to automatically build, upload and publish extension wheels.
Once your pull request is merged into main branch, a new pull request will be created to update src/index.json automatically.
You only need to update the version information in file setup.py and historical information in file HISTORY.rst in your PR but do not modify src/index.json.

[azure-client-tools-bot-prd]

️✔️Azure CLI Extensions Breaking Change Test

️✔️Non Breaking Changes

[azure-client-tools-bot-prd]

Hi @copilot,
Please write the description of changes which can be perceived by customers into HISTORY.rst.
If you want to release a new extension version, please update the version in setup.py as well.

[yonzhan]

Container Apps