update include_bots_in_aggregates default value to True

[lsabor]

closes #3448

After this is complete, all new questions written will have the new default value
does not effect existing questions

[CodexVeritas]

Before we implement this:

1. We need to change the filtering in forecasting-tools and auto quesitons to not use "include bots in aggregate" as a proxy for whether the question is an AIB question
2. If we apply this to all open questions, then we also need to make sure to remove bot forecasts on the 'practice questions' I've given to bot makers, ask bots not to use these as practice questions, and make a practice question tournament.
3. We have replaced the CP_will_rise question in auto-questions (or have decided its ok to try to predict the bot's community prediction on some questions)

Getting thoughts from Sylvain, but we may want to implement this starting Jan 1st. See conversation here: https://metaculus.slack.com/archives/C0679GQ0N56/p1757955070595839

[elisescu]

Code LGTM, but let's not merge before syncing with the Product team and getting a 👍

[lsabor]

We should move this conversation over to slack since it's easier for Sylvain to track and participate. Leaving this to only be discussion of the actual PR.

[hlbmtc]

LGTM, but I'd remove migration

[CodexVeritas]

Just for context: this issue is a blocker.