Block Supports: Add typography text indent support

[aaronrobertshaw]

This ticket tracks the backport of PHP files for the following Gutenberg updates:

​https://github.com/WordPress/gutenberg/pull/73114

These updates include the PHP and theme.json changes to add typography text indent block support.

Trac ticket: https://core.trac.wordpress.org/ticket/64326#ticket

### Description

Adds support for text-indent styles for Typography block supports.

​https://github.com/WordPress/gutenberg/pull/73114

### Test Instructions

1. Adopt typography.textIndent block support for a dynamic block via its block.json file
2. Add a typography.textIndent value for the chosen test block in your theme.json file
3. Create a post with the test block type
4. Confirm the global style is applied to your test block

This works as described and matches the diff between ​https://github.com/WordPress/gutenberg/pull/74889

I'm just wondering whether we need to add test coverage for the new support and its expected output.

+1 this is testing nicely for me, too, should be good once it's got a couple tests, I think.

I've added some tests to cover both the block support and global styles angles. Let me know if they hit the spot.

I've added some tests to cover both the block support and global styles angles. Let me know if they hit the spot.

LGTM. I'll rebase quickly to fix conflicts

[ramonopoly]

In 61632:

Block Supports: Add text indent to typography supports

This commit adds CSS text-indent support for paragraph blocks with traditional typography conventions - subsequent paragraphs get first-line indented in LTR languages, with an option to indent all paragraphs (default for RTL languages).

Text indentation is a fundamental typography feature. Traditional print typography conventions dictate that only subsequent paragraphs (not the first) should have their first line indented in LTR languages, while RTL languages typically indent all paragraphs. This feature enables proper typographic styling that matches publishing standards.

Props aaronrobertshaw, ramonopoly, andrewserong, wildworks, matveb, skorasaurus, greenshady, kjellr.

Fixes #64326.

Committed in r61632 and ​https://github.com/WordPress/wordpress-develop/commit/d082b28af2f2cd16601a9d480ab985ed8e5d7020

[audrasjb]

This is worth mentioning in the Field Guide.
Also adding needs-dev-note just in case we can mention it in a more general note.

[aaronrobertshaw]

A dev note has already been published for this:
​https://make.wordpress.org/core/?p=121744