[Dev Container] Init the dev container solution

[Sorgann]

Describe your changes

Make it easier to modify the solution by adding a devcontainer tool. It allows you to launch a container from vscode to launch homeassistant with a task. Dirigera is already available to test.

Checklist before submitting a pull request

• [N/A] Updated base lib and added the required version in the requirements.txt and manifest.json

Checklist for reviewer

• Select "Squash and merge" to keep commit timeline clean

[Sorgann]

@nrbrt Do you think you will merge this pull request ?
It allows to start the development faster, mainly to test our code

[nrbrt]

Hi @Sorgann, thanks for this PR! I'm always open to contributions that make development easier for the community.

Before we can merge this, there are a few issues that need to be addressed:

1. Typo in devcontainer.json: "postStawsrtCommand" should be "postStartCommand" — currently this hook won't execute at all.

2. Python 3.14 in .python-version: Python 3.14 hasn't been released yet (expected October 2026). This should be set to a currently available version, e.g. 3.12 or 3.13.

3. Scripts missing executable permissions: script/setup and script/bootstrap need chmod +x to be executable.

Could you update the PR with these fixes? Happy to merge once they're resolved.