feat: add Otter notice in FSE editor for Blocks CSS

[HardeepAsrani]

Closes https://github.com/Codeinwp/otter-internals/issues/120 and https://github.com/Codeinwp/otter-internals/issues/194.

Summary

This adds a Notice to Site Editor when Blocks CSS is being used alone. Clicking on the button installs to Otter in a new tab.

Screenshots

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Test instructions

• Confirm the notice appears if:
  • When using Blocks CSS in Site Editor
  • Not inside normal Post Editor or when used as part of Otter

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Checklist before the final review

• Included E2E or unit tests for the changes in this PR.
• Visual elements are not affected by independent changes.
• It is at least compatible with the minimum WordPress version.
• It loads additional script in frontend only if it is required.
• Does not impact the Core Web Vitals.
• In case of deprecation, old blocks are safely migrated.
• It is usable in Widgets and FSE.
• Copy/Paste is working if the attributes are modified.
• PR is following the best practices

[HardeepAsrani]

@ineagu Let me know if you have any feedback on the wording.

[pirate-bot]

Bundle Size Diff

Package	Old Size	New Size	Diff
Animations	263.48 KB	263.48 KB	0 B (0.00%)
Blocks	1.52 MB	1.52 MB	0 B (0.00%)
CSS	92.73 KB	93.18 KB	465 B (0.49%)
Dashboard	195.5 KB	195.5 KB	0 B (0.00%)
Onboarding	153.14 KB	153.14 KB	0 B (0.00%)
Export Import	90.21 KB	90.21 KB	0 B (0.00%)
Pro	361.57 KB	361.57 KB	0 B (0.00%)

[pirate-bot]

Plugin build for 44aea76 is ready 🛎️!

• Download Otter – Page Builder Blocks & Extensions for Gutenberg - Production ~ Development
• Download Otter Pro - Production ~ Development
• Download Blocks Animation - Production ~ Development
• Download Blocks CSS - Production ~ Development
• Download Blocks Export Import - Production ~ Development

[pirate-bot]

E2E Tests

Playwright Test Status:

Performance Results

serverResponse: 240.8, firstPaint: 159.05, domContentLoaded: 1566.65, loaded: 1567.5, firstContentfulPaint: 3510.8, firstBlock: 6802, type: 12.36, minType: 10.73, maxType: 14.55, typeContainer: 9.09, minTypeContainer: 7.51, maxTypeContainer: 11.23, focus: 34.33, minFocus: 27.86, maxFocus: 53.19, inserterOpen: 24.11, minInserterOpen: 20.95, maxInserterOpen: 32.82, inserterSearch: 0.76, minInserterSearch: 0.61, maxInserterSearch: 0.92, inserterHover: 2.93, minInserterHover: 2.53, maxInserterHover: 3.86, listViewOpen: 146.33, minListViewOpen: 135.75, maxListViewOpen: 165.15

[ineagu]

looks great.

[pirate-bot]

🎉 This PR is included in version 3.0.0 🎉

The release is available on GitHub release

Your semantic-release bot 📦🚀