Updated: use staging activity URL by default

[Miexil]

What does this PR do?

Modifies naming of the activityURL so that it can be overwritten by parent projects.

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[phndiaye]

For the configuration, what about using getOwnConfig instead ?

It's setup like this in settings-web: https://github.com/upfluence/upfluence-web/blob/670cbe2c5f6f33c5a6e629f20a2748b31c480989/packages/settings-web/index.js#L59-L87.

Then where needed, it would getOwnConfig().activityUrl (which i would've kept to backendActivityUrl, personally). I believe we skipped the backend prefix for variables leading to frontends (like identityUrl for example)

This also means the addon will be responsible of its setup without having to pass the variable through parent apps.

[phndiaye]

For the configuration, what about using getOwnConfig instead ?

It's setup like this in settings-web: upfluence/upfluence-web@670cbe2/packages/settings-web/index.js#L59-L87.

Then where needed, it would getOwnConfig().activityUrl (which i would've kept to backendActivityUrl, personally). I believe we skipped the backend prefix for variables leading to frontends (like identityUrl for example)

This also means the addon will be responsible of its setup without having to pass the variable through parent apps.

Discussed live, let's keep it as is for now ;)