Expose the insert macro action

With XWIKI-24048 we can now edit existing macro calls but BlockNote doesn't provide a way to insert a new macro call. XWIKI-23863 is going to provide quick actions for inserting specific macros but until then, and maybe even after that, we need a way to open the Select Macro modal. Even if we add quick actions for specific macros, we might not want to expose deprecated or technical macros as quick actions so having a way to insert them for edge cases is still important.

The insert macro action could be exposed:

• on the context toolbar, when some text is selected (e.g. to make the selected text an information box)
• on the quick actions dropdown