ci: add npm to dependabot config

[sammy200-ui]

now we also have npm dependencies with github actions as well !!

fixes #200

[Copilot]

Pull request overview

Adds npm dependency update checks to the existing Dependabot configuration so the repository’s Node.js dependencies receive automated weekly update PRs alongside GitHub Actions updates.

Changes:

• Extend .github/dependabot.yml to include the npm ecosystem.
• Configure npm updates to run weekly for the root directory (/).

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[robertodauria]

Please align the configuration with what we use on other JS repositories - for example: https://github.com/m-lab/ndt7-js/blob/main/.github/dependabot.yml

[sammy200-ui]

done with the changes , also changed the old github action to match the example you gave !!

[bassosimone]

@sammy200-ui FYI we use conventional commits (https://www.conventionalcommits.org/en/v1.0.0/). I edited your pull request title to match this was of expressing commits. I suggest you take a look.

[robertodauria]

LGTM. Thanks.