Set up CodeRabbit for AI code reviews (#15813)

.coderabbit.yaml

@@ -0,0 +1,26 @@
+# yaml-language-server: $schema=https://coderabbit.ai/integrations/coderabbit-overrides.v2.json
+
+# Schema with docs on the properties: https://coderabbit.ai/integrations/coderabbit-overrides.v2.json. Docs:
+# https://docs.coderabbit.ai/guides/configure-coderabbit. This only includes overrides for defaults and mandatory
+# elements.
+
+early_access: true
+reviews:
+  # This would allow the bot to approve a PR. Since we always need a human to approve (and merge), we don't use this,
+  # so it doesn't add noise to the pull request filters like
+  # https://github.com/OrchardCMS/OrchardCore/pulls?q=is%3Apr+is%3Aopen+review%3Anone.
+  request_changes_workflow: false
+  # Very rarely contains useful info, mostly is just noise.
+  high_level_summary: false
+  # We really don't need a poem.
+  poem: false
+  # The review status comment is useful for debugging but not otherwise.
+  review_status: false
+  # The code walkthrough's text may take a lot of space, so collapsing it is nicer UX.
+  collapse_walkthrough: true
+  # On-demand reviews are available but PRs are not reviewed automatically.
+  auto_review:
+    enabled: false
+    drafts: false
+chat:
+  auto_reply: true

OrchardCore.sln

@@ -252,6 +252,7 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "OrchardCore.Workflows.Abstr
 EndProject
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Solution Items", "Solution Items", "{68F6113F-2F08-4412-B5E7-41B7164A0C7F}"
 	ProjectSection(SolutionItems) = preProject
+		.coderabbit.yaml = .coderabbit.yaml
 		.editorconfig = .editorconfig
 		gulpfile.js = gulpfile.js
 		package.json = package.json

src/docs/guides/contributing/contributing-code.md

@@ -67,6 +67,7 @@ All code submissions will be reviewed and tested by the core team, and only thos
 - Feel free to mark conversations that you addressed to keep track of them with an emoji or otherwise, just don't resolve them.
 - Please keep conversations happening in line comments in those convos, otherwise, communication will be a mess. If you have trouble finding them, see [this video](https://github.com/OrchardCMS/OrchardCore/pull/14749#issuecomment-1917976028).
 - When you're done addressing all feedback of a review, click ["Re-request review"](https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/incorporating-feedback-in-your-pull-request#re-requesting-a-review) in the top-right corner for each reviewer when you're ready for another round of review, so they know that you're done.
+- [CodeRabbit](https://coderabbit.ai/) is available for AI on-demand code reviews, which they graciously provide for us as an open-source project for free. You can ask the bot for a code review with a `@coderabbitai review` comment under any pull request. You can have a conversation with it under its comments too. Note that AI code reviews can help, but are frequently incorrect; use your best judgment.
 
 !!! tip
     Do you want to demo what you've done to others, to showcase your work and to gather feedback? Join one of [our meetings](../../resources/meeting/README.md).

src/docs/guides/contributing/reviewing-pull-requests.md

@@ -24,6 +24,7 @@ If the PR is coming from a fork, working with its code locally won't be as trivi
 - Be sure to merge PRs that don't need a second opinion. This is especially important for external contributors who can't merge their PRs. Keeping PRs open will make them collect merge conflicts and make the contributor demotivated.
 - Be especially patient and encouraging with first-time contributors. This is indicated by such a flag on the PR.
 - You can add the [Feedback section](contributing-code.md) to your review comment (i.e. the one that you send your per-line comments with) to remind the author about the practices.
+- You can ask [CodeRabbit](https://coderabbit.ai/) for an AI code review with a `@coderabbitai review` comment under any PR.
 
 ## Backporting Pull Requests to Another Branch