Add the AI Code Review recipe and onboarding documentation

Prepared with AI assistance and reviewed against the Recipe behavior and installation tests.

Current status

The implementation is available in MR!1, targeting 1.x. Public CI passed all seven automatic jobs. The Functional suite executed two tests and 40 assertions with no failures or skipped tests on PHP 8.3.36 and Drupal 11.4.12. MR!1 was squash-merged into 1.x as 8912b462c3f51b752ad0a70b5723e17f76805296 after review and approval by yas. The accepted commit message and file tree match the reviewed candidate. Post-merge CI also passed all seven automatic jobs and the two Functional tests with 40 assertions. Credits are saved for yas and ai_yas. Recipe 1.0.0-alpha1 is published. Both advertised archives have been inspected; their seven files match the accepted source except packaging-only LICENSE heading whitespace. The Composer distribution matches all seven accepted files exactly.

Problem/Motivation

Site builders need a repeatable way to prepare an AI Code Review UI site and connect it to a separate AI Code Review Server site.

Proposed resolution

• Add the drupal/ai_code_review Recipe for Drupal 11.4 and UI 1.x.
• Install the UI module only. Create a dedicated reviewer role with Add, View, and List permissions, preserving existing role properties and unrelated permissions.
• Document that View access covers reviews across the UI site. Leave edit, delete, administration, and optional cancellation permissions to the site administrator.
• Document separate Server installation, HTTPS, authentication, provider registration, and connection setup without including credentials or deployment-specific URLs.
• Add functional Recipe application tests and standard Drupal CI.

Release follow-up

• Published package and normal Composer installation verification are complete. Application and reapplication on clean and configured sites passed, including existing role and connection-setting preservation.
• Separate-site verification found missing default policy and review-list configuration on fresh Recipe installations. Functional release acceptance remains incomplete until #3636118: Fix UI configuration imports during Recipe application is resolved and verified. The published alpha tag remains unchanged.

Local validation

On a fresh Drupal 11.4.12 site with the published UI 1.0.0-alpha1, Recipe application and reapplication succeeded. Two functional tests passed with 40 assertions. Existing site configuration and role properties were preserved. The documented Composer command succeeded with both alpha packages explicitly required, without lowering global minimum stability. PHP syntax and Drupal coding checks passed. Eight dependency deprecation notices remain; no provider API calls were made. Public CI also passed on PHP 8.3. These pre-release results are distinct from the published-package checks recorded above.