feat(meeting-creation): only allow bestuursorganen active at planned start date

[elpoelma]

Overview

This PR adjusts the logic of the meeting creation dialog:

• Only allow the selection of 'bestuursorganen' which are active on the selected 'planned start' date
• When modifying the 'planned start' date, clear the 'bestuursorgaan' if necessary.

Additionally, this PR also modernizes the administrative-body-select component a bit (usage of trackedFunction and ensuring reactivity)

connected issues and PRs:

Should reduce issues like these: https://binnenland.atlassian.net/browse/GN-5216

How to test/reproduce

• Start the app
• Log in as a municipality
• Open the meeting creation dialog
• Ensure that the list of 'bestuursorgaan' options changes based on the 'planned start` that is selected
• Ensure that the 'bestuursorgaan' field is cleared when you select a 'planned start' date on which the 'bestuursorgaan' is not active
• Meeting creation itself should still work as before

Challenges/uncertainties

• This PR only applies this logic on the meeting creation flow. It doesn't allow for editing the 'bestuursorgaan' after creation.
• I created a seperate Jira ticket to track the feature to be able to edit the bestuursorgaan after the meeting creation: https://binnenland.atlassian.net/browse/GN-5218 . This is, however, not trivial to implement.

Checks PR readiness

• UI: works on smaller screen sizes
• UI: feedback for any loading/error states
• Check cancel/go-back flows
• Check database state correct when deleting/updating (especially regarding relationships)
• changelog
• npm lint
• no new deprecations