fix(devcontainer): configure host networking to fix runtime connection

[llamantino]

…n issue

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• Include this change in the Release Notes. If checked, you must provide an end-user friendly description for your change below

End-user friendly description of the problem this fixes or functionality this introduces.

Fixes a networking issue in the devcontainer setup where the app failed to connect to the runtime container, resulting in connection refused errors.

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Summarize what the PR does, explaining any non-trivial design decisions.

Adds "runArgs": ["--network=host"] so the app can access the localhost-bound port exposed by the runtime container.

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Link of any specific issues this addresses:

[enyst]

Thank you!