[Docs] Extract release documentation to RELEASE.md

README is generally better kept focused on information that is most valuable to users.
For that reason, release procedures that are not relevant to end users have been moved to
a separate RELEASE.md file.

Author: koic

README.md

@@ -925,16 +925,3 @@ The client provides a wrapper class for tools returned by the server:
 - `MCP::Client::Tool` - Represents a single tool with its metadata
 
 This class provides easy access to tool properties like name, description, input schema, and output schema.
-
-## Releases
-
-This gem is published to [RubyGems.org](https://rubygems.org/gems/mcp)
-
-Releases are triggered by PRs to the `main` branch updating the version number in `lib/mcp/version.rb`.
-
-1. **Update the version number** in `lib/mcp/version.rb`, following [semver](https://semver.org/)
-1. **Update CHANGELOG.md**, backfilling the changes since the last release if necessary, and adding a new section for the new version, clearing out the Unreleased section
-1. **Create a PR and get approval from a maintainer**
-1. **Merge your PR to the main branch** - This will automatically trigger the release workflow via GitHub Actions
-
-When changes are merged to the `main` branch, the GitHub Actions workflow (`.github/workflows/release.yml`) is triggered and the gem is published to RubyGems.