Bump gutenberg SHA to d18be22

[fushar]

Trac ticket: https://core.trac.wordpress.org/ticket/65382

This PR bumps the bundled Gutenberg to commit d18be22, which contains WordPress/gutenberg#78397.

This is necessary to backport the updated --wp-admin-theme-color colors, so that the admin bar, sidebar, and primary button background all have the same color. See the linked Trac issue for more details.

The rest of the changes are generated, via npm run gutenberg:download.

Screenshot

(See the bottom-right button and the bottom-right gutter/chrome color)

Before	After

Use of AI Tools

AI assistance: Yes
Tool(s): Claude Code
Model(s): Fable
Used for: Updating the SHA and running the download script .

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[fushar]

Hi @adamsilverstein , I noticed that you have a similarly open PR here: #12009.

My PR here is pinning to a hash that's seemingly newer to yours. I believe my hash already contains React 19 revert (WordPress/gutenberg#78940), so I believe it's safe.

Can you help confirm? Should we just use this new PR instead of yours? Thanks!

[adamsilverstein]

@fushar fine to use yours instead of mine. I'll close my PR. We weren't able to merge due to the modified files that weren't meant for trunk. You can read more on this in the linked PR from @desrosj - I was on hold until his PR to fix the build exclusions landed. I'm mostly out this week so please feel free to push this forward. It's also blocking me from backporting changes.

[fushar]

@adamsilverstein Thanks for the reply. But I can't seem to find the linked PR that you mentioned :)

Also could you confirm that I did the right thing here? I.e. update the hash and run npm run gutenberg:download?

[adamsilverstein]

Apologies for the cryptic reply, I'm replying from my phone. The pr I was talking about is WordPress/gutenberg#76715 and it looks like it was merged. And yes, that looks like the right command.