App based tool additions

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Feature request

Which Nextcloud Version are you currently using: (see administration page)

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I'm not sure if this is actually already a thing or not, but I noticed all the tools in here seem to be implemented in this app. That means that if an app wants to have its tools in this, they have to. Make a pull request and implement it in here, right?

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I think it would be nice to have an endpoint where an app either a back-end app as in a Harp app, or a regular PHP app could add tools. For instance, a PHP app could register a tool even if it was a 3rd party app. Of course, this would be managed in the settings of Context agent which apps would be turned on or not.
That way, if an app wants to add a tool, instead of having to make a pull request and work within this repository, any app would be able to automatically put this in.

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Put it in manually in this app.
Additional context
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Again, I sure if this already exists.

I feel like this app is mature enough and also is widely enough used most likely that it makes sense to be able to let other apps register their own tools, especially for the sake of if other apps decide to use this more often and provide more tools, then eventually this app can just grow and grow in size of tools that may not even be added by the user.
It makes sense to have many apps provide a connector to one app, then to have one app provide a connector for many apps which a user may not even use. That way only apps that the user has active is contributing to making the tool size bigger.

No files, tests, or entry points are named in the request. Start by tracing how tools are currently registered and how Context agent settings enable them; then define the registration behavior for third-party apps and verify that an external app can add a tool and be disabled by the user.