What?

Fixes #71709
Part of #71517

Context: #71512 (comment)

This PR disables transforms and inspector controls when one or more or all blocks in multi-selection are "section blocks".

Why?

As part of #71517, a "section block" — for example patterns or template parts — is displayed in content only mode.

Content only mode describes an editing mode in which the inner block tree of section blocks are filtered to only display common content blocks, and with limited editing in the toolbar and inspector sidebar.

The different toolbar and inspector states of section blocks make them incompatible with regular blocks.

The idea is to make things more consistent with other "incompatible" multi-block combinations - in these cases n blocks is displayed only in the sidebar.

How?

Checking for section blocks in the getSelectedBlockClientIds() return value (Array).

Testing Instructions

Switch on the patterns + content only experiment:

1. Insert a few patterns and a few blocks
2. Using the list view menu, select the patterns. Check that the inspector does not display any styles controls or others.
3. Select a pattern and regular block. Check that you cannot transform them in the toolbar, and that the inspector doesn't display controls.

Screenshots or screencast

Before

After