Create Confluence documentation about macro nesting to improve customer experience

Issue Summary

Currently, there is no easy and quick way for customers and support to reliably see which macros can and cannot be nested.

The behavior is uncertain with each macro combination. I can, for example, nest a Page Include macro within an Expand Macro. However, nesting an iFrame into an Expand Macro is not possible.

Ideally, for a better customer and support experience, what works and does not work would be listed in our official documentation.

Having this documentation is important for the current situation because:

1. It improves support reliability
2. It helps the customers to self-serve
3. Clarifies our platform ins and outs

Steps to Reproduce

1. Create a page
2. Try to nest a macro

Expected Results

It will not be possible to nest any macro / It will be possible to nest all macros

Actual Results

Some macros can not be nested, some can. Some macros that can not be nested with some configuration, can be nested using another.

Workaround

Test the nesting case by case to confirm the behavior.