Add first party mode datastore.

[ankitrox]

Summary

Addresses issue:

• Create First-Party Mode Partial Datastore in Core Site #9628

Relevant technical choices

PR Author Checklist

• My code is tested and passes existing unit tests.
• My code has an appropriate set of unit tests which all pass.
• My code is backward-compatible with WordPress 5.2 and PHP 7.4.
• My code follows the WordPress coding standards.
• My code has proper inline documentation.
• I have added a QA Brief on the issue linked above.
• I have signed the Contributor License Agreement (see https://cla.developers.google.com/).

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Code Reviewer Checklist

• Run the code.
• Ensure the acceptance criteria are satisfied.
• Reassess the implementation with the IB.
• Ensure no unrelated changes are included.
• Ensure CI checks pass.
• Check Storybook where applicable.
• Ensure there is a QA Brief.
• Ensure there are no unexpected significant changes to file sizes.

Merge Reviewer Checklist

• Ensure the PR has the correct target branch.
• Double-check that the PR is okay to be merged.
• Ensure the corresponding issue has a ZenHub release assigned.
• Add a changelog message to the issue.

[github-actions]

Build files for 00f8de9 have been deleted.

[github-actions]

Size Change: +359 B (+0.02%)

Total Size: 1.88 MB

Filename	Size	Change
./dist/assets/js/googlesitekit-ad-blocking-recovery-********************.js	55 kB	-1 B (0%)
./dist/assets/js/googlesitekit-adminbar-********************.js	34.6 kB	-1 B (0%)
./dist/assets/js/googlesitekit-datastore-site-********************.js	20.9 kB	+359 B (+1.75%)
./dist/assets/js/googlesitekit-datastore-user-********************.js	27.3 kB	+2 B (+0.01%)
./dist/assets/js/googlesitekit-entity-dashboard-********************.js	81.9 kB	-2 B (0%)
./dist/assets/js/googlesitekit-main-dashboard-********************.js	161 kB	-1 B (0%)
./dist/assets/js/googlesitekit-modules-ads-********************.js	33.4 kB	-2 B (-0.01%)
./dist/assets/js/googlesitekit-modules-adsense-********************.js	117 kB	+2 B (0%)
./dist/assets/js/googlesitekit-modules-analytics-4-********************.js	184 kB	+5 B (0%)
./dist/assets/js/googlesitekit-modules-********************.js	22.2 kB	+1 B (0%)
./dist/assets/js/googlesitekit-modules-search-console-********************.js	64.9 kB	+2 B (0%)
./dist/assets/js/googlesitekit-modules-sign-in-with-google-********************.js	24.7 kB	-1 B (0%)
./dist/assets/js/googlesitekit-modules-tagmanager-********************.js	32.2 kB	-2 B (-0.01%)
./dist/assets/js/googlesitekit-settings-********************.js	126 kB	+6 B (0%)
./dist/assets/js/googlesitekit-wp-dashboard-********************.js	62.6 kB	-8 B (-0.01%)

ℹ️ View Unchanged

Filename	Size
./dist/assets/css/googlesitekit-admin-css-********************.min.css	60.3 kB
./dist/assets/css/googlesitekit-adminbar-css-********************.min.css	11.8 kB
./dist/assets/css/googlesitekit-authorize-application-css-********************.min.css	846 B
./dist/assets/css/googlesitekit-wp-dashboard-css-********************.min.css	8.2 kB
./dist/assets/js/32-********************.js	2.76 kB
./dist/assets/js/33-********************.js	2.25 kB
./dist/assets/js/34-********************.js	3.64 kB
./dist/assets/js/35-********************.js	935 B
./dist/assets/js/36-********************.js	893 B
./dist/assets/js/37-********************.js	1.61 kB
./dist/assets/js/38-********************.js	1.57 kB
./dist/assets/js/39-********************.js	1.61 kB
./dist/assets/js/40-********************.js	1.59 kB
./dist/assets/js/41-********************.js	1.83 kB
./dist/assets/js/42-********************.js	3.11 kB
./dist/assets/js/analytics-advanced-tracking-********************.js	901 B
./dist/assets/js/googlesitekit-activation-********************.js	24 kB
./dist/assets/js/googlesitekit-api-********************.js	10.1 kB
./dist/assets/js/googlesitekit-components-gm2-********************.js	6.17 kB
./dist/assets/js/googlesitekit-components-gm3-********************.js	10.1 kB
./dist/assets/js/googlesitekit-consent-mode-********************.js	25.6 kB
./dist/assets/js/googlesitekit-data-********************.js	2.37 kB
./dist/assets/js/googlesitekit-datastore-forms-********************.js	8.97 kB
./dist/assets/js/googlesitekit-datastore-location-********************.js	2.08 kB
./dist/assets/js/googlesitekit-datastore-ui-********************.js	10.1 kB
./dist/assets/js/googlesitekit-events-provider-contact-form-7-********************.js	646 B
./dist/assets/js/googlesitekit-events-provider-easy-digital-downloads-********************.js	624 B
./dist/assets/js/googlesitekit-events-provider-mailchimp-********************.js	630 B
./dist/assets/js/googlesitekit-events-provider-ninja-forms-********************.js	712 B
./dist/assets/js/googlesitekit-events-provider-optin-monster-********************.js	675 B
./dist/assets/js/googlesitekit-events-provider-popup-maker-********************.js	634 B
./dist/assets/js/googlesitekit-events-provider-woocommerce-********************.js	657 B
./dist/assets/js/googlesitekit-events-provider-wpforms-********************.js	633 B
./dist/assets/js/googlesitekit-i18n-********************.js	3.93 kB
./dist/assets/js/googlesitekit-modules-pagespeed-insights-********************.js	22.8 kB
./dist/assets/js/googlesitekit-modules-reader-revenue-manager-********************.js	41.1 kB
./dist/assets/js/googlesitekit-notifications-********************.js	22.8 kB
./dist/assets/js/googlesitekit-polyfills-********************.js	377 B
./dist/assets/js/googlesitekit-splash-********************.js	68.9 kB
./dist/assets/js/googlesitekit-user-input-********************.js	43.7 kB
./dist/assets/js/googlesitekit-vendor-********************.js	322 kB
./dist/assets/js/googlesitekit-widgets-********************.js	96.2 kB
./dist/assets/js/runtime-********************.js	1.4 kB

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[hussain-t]

Thanks, @techanvil. This almost looks good. However, I've left a couple of comments for your review.

[hussain-t]

Excellent work, @techanvil! LGTM 👍