docs: create Contributing to Renovate page (#25238)

docs/usage/.pages

@@ -54,3 +54,4 @@ nav:
       - 'Known Limitations': 'known-limitations.md'
       - 'Release notes for major versions': 'release-notes-for-major-versions.md'
   - About Us: 'about-us.md'
+  - Contributing to Renovate: 'contributing-to-renovate.md'

docs/usage/contributing-to-renovate.md

+# Contributing to Renovate
+
+Thank you for thinking of contributing to Renovate!
+The [`docs/development/` directory of the `renovatebot/renovate` repository](https://github.com/renovatebot/renovate/tree/main/docs/development) has all the developer-facing documentation.
+
+## I want to write code
+
+### Read this first
+
+1. [Contributing guide](https://github.com/renovatebot/renovate/blob/main/.github/contributing.md)
+1. [Best practices](https://github.com/renovatebot/renovate/blob/main/docs/development/best-practices.md)
+1. [Local Development](https://github.com/renovatebot/renovate/blob/main/docs/development/local-development.md) or [Remote Development](https://github.com/renovatebot/renovate/blob/main/docs/development/remote-development.md)
+
+### Creating/editing Renovate preset
+
+1. [Creating/editing Renovate presets](https://github.com/renovatebot/renovate/blob/main/docs/development/creating-editing-renovate-presets.md)
+
+### Adding a new package manager
+
+1. [Adding a Package Manager](https://github.com/renovatebot/renovate/blob/main/docs/development/adding-a-package-manager.md)
+
+### Background information
+
+1. [Design Decisions](https://github.com/renovatebot/renovate/blob/main/docs/development/design-decisions.md)
+1. [Zod schema guideline](https://github.com/renovatebot/renovate/blob/main/docs/development/zod.md)
+1. [Branches and commits behavior](https://github.com/renovatebot/renovate/blob/main/docs/development/branches-commits.md)
+1. [Configuration](https://github.com/renovatebot/renovate/blob/main/docs/development/configuration.md)
+1. [Static Data](https://github.com/renovatebot/renovate/blob/main/docs/development/static-data.md)
+1. [How to bump Renovate to next NodeJS LTS release](https://github.com/renovatebot/renovate/blob/main/docs/development/bump-node-major.md)
+
+## I want to write documentation
+
+Read the [Contributing guide](https://github.com/renovatebot/renovate/blob/main/.github/contributing.md), and the [Renovate style guide](https://github.com/renovatebot/renovate/blob/main/docs/development/style-guide.md).
+
+## I want to triage incoming discussions
+
+Start by reading:
+
+1. [Contributing guide](https://github.com/renovatebot/renovate/blob/main/.github/contributing.md)
+1. [Triage guide](https://github.com/renovatebot/renovate/blob/main/docs/development/triage-guide.md)
+1. [Issue labeling](https://github.com/renovatebot/renovate/blob/main/docs/development/issue-labeling.md)
+
+You may need to direct a Renovate user to one of these pages:
+
+1. [About minimal reproductions](https://github.com/renovatebot/renovate/blob/main/docs/development/minimal-reproductions.md)
+1. [New package manager questionnaire](https://github.com/renovatebot/renovate/blob/main/docs/development/new-package-manager-template.md)
+1. [Help Us Help You](https://github.com/renovatebot/renovate/blob/main/docs/development/help-us-help-you.md)