[Backport to release/11.3] Fix Interactivity API directive IDs for WordPress 7.2 - #70087

This PR is a cherry-pick of #70076 to release/11.3.

Original PR Description

Submission Review Guidelines:

• I have followed the WooCommerce Contributing Guidelines and the WordPress Coding Standards.
• I have checked related Pull Requests; this intentionally extracts the Interactivity API fixes from Restore block compatibility with WordPress 7.2 #70075 for separate review.
• I have reviewed my code for security best practices.
• I have assessed the impact of this change and followed the applicable review requirements.
• Following the above guidelines will result in quick merges and clear and detailed feedback when appropriate.

Changes proposed in this Pull Request:

Gutenberg PR #84098 removes support for two-hyphen unique IDs on Interactivity API lifecycle directives, so WordPress 7.2 skips WooCommerce callbacks using data-wp-init--id and data-wp-watch--id. The syntax was announced in the WordPress 6.9 developer note.

I discovered this issue fixing E2E tests failure on this job: https://github.com/woocommerce/woocommerce/actions/runs/39537238981

Screenshots or screen recordings:

Restores existing storefront behavior; no visual design changes.

How to test the changes in this Pull Request:

1. Ensure that the CI is green

2. Run these five regression tests against WordPress 7.2:

WP_ENV_CORE=https://wordpress.org/wordpress-7.2-beta1.zip \
WP_ENV_PHP_VERSION=8.3
pnpm --filter=@woocommerce/plugin-woocommerce env:start:blocks

WP_ENV_CORE=https://wordpress.org/wordpress-7.2-beta1.zip \
WP_ENV_PHP_VERSION=8.3 \
pnpm --filter=@woocommerce/plugin-woocommerce test:e2e:blocks:serial \
  tests/e2e/tests/blocks/add-to-cart-with-options/add-to-cart-with-options.block_theme.spec.ts \
  tests/e2e/tests/blocks/product-filters/product-filters-frontend.block_theme.spec.ts \
  tests/e2e/tests/blocks/product-gallery/inner-blocks/product-gallery-large-image/product-gallery-large-image.block_theme.spec.ts \
  tests/e2e/tests/blocks/product-gallery/inner-blocks/product-gallery-thumbnails/product-gallery-thumbnails.block_theme.spec.ts 
```

Testing that has already taken place:

• Docker wp-env, PHP 8.3, block theme, and WooCommerce sample products on WordPress 7.2 beta 1 and 7.1. The focused branch's seven PHP files were mounted into the test environment independently of the other changes in Restore block compatibility with WordPress 7.2 #70075.
• Existing E2E regressions passed on both versions: variation validation/add-to-cart, synchronizing multiple Product Filters blocks, both variable-product gallery flows, thumbnail overflow, and Mini-Cart item counts (six test cases per version, plus setup).
• lint:php:changes, lint:changes:branch, and PHPStan for all seven PHP files passed. No PHPStan baseline changes. git diff --check is clean.
• Multisite, third-party extensions, and gallery video playback were not tested. No database, option, hook, or install-path changes.

Milestone

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Changelog entry

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Use of AI Tools

Codex extracted the directive fixes from #70075 and assisted with the changelog, PR description, and local validation. Independent human review is pending.