Page: add option to subscribe to toolbar title click

[jakobe]

Which issue does this PR close?

This PR closes #3075

What is the new behavior?

It's already possible to subscribe to Header.onTitleClick() which also is emitted on toolbar title click, but in virtual scrolling scenarios the header gets removed from the DOM and the component instance destroyed, which prevents the event handler from being triggered.

This PR adds a toolbarTitleClick event/output property.
It also adds a hasInteractiveTitle prop to support overriding when the toolbar should be styled as clickable (i.e. cursor: pointer)

Does this PR introduce a breaking change?

• Yes
• No

Are there any additional context?

No.

Checklist:

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Reminders

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Review

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• [ ] Request that the changes are UX reviewed (only necessary if your PR introduces visual changes)

When the pull request has been approved it will be merged to develop by Team Kirby.

[mark-drastrup]

Nice work!