chore: update branch references for main/legacy rename (ENG-2105) (#125)

Update CI triggers, CLAUDE.md, CONTRIBUTING.md, and README.md to
reflect the branch rename: develop → main, main → legacy.

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: prestwich

.github/workflows/rust.yml

@@ -3,7 +3,7 @@ name: CI # Continuous Integration
 on:
   workflow_dispatch:
   push:
-    branches: [main]
+    branches: [main, legacy]
   pull_request:
 
 # simplest example of using the rust-base action

CLAUDE.md

@@ -2,8 +2,8 @@
 
 ## Branches
 
-The `main` branch is in maintenance and bug-fix mode. The `develop` branch
-contains current work.
+The `main` branch contains current work. The `legacy` branch is under
+long-term maintenance and may receive active work.
 
 ## Commands
 

CONTRIBUTING.md

@@ -22,6 +22,11 @@ We maintain code quality and style standards, and require commit signing. This
 option allows us to make small changes to your PR to bring it in line with
 these standards. It helps us get your PR in faster, and with less work from you.
 
+### Branching
+
+PRs should target the `main` branch by default. The `legacy` branch is under
+long-term maintenance and accepts maintenance and backport PRs.
+
 ## Development Basics
 
 Before submitting a PR we recommend you run the following commands to ensure

README.md

@@ -3,8 +3,8 @@
 [![CI](https://github.com/init4tech/node-components/actions/workflows/rust.yml/badge.svg)](https://github.com/init4tech/node-components/actions/workflows/rust.yml)
 [![License: MIT](https://img.shields.io/badge/License-MIT-blue.svg)](LICENSE)
 
-> **Note:** The `main` branch is in maintenance and bug-fix mode. The
-> `develop` branch contains current work.
+> **Note:** The `legacy` branch is under long-term maintenance and may receive
+> active work. The `main` branch contains current work.
 
 A collection of components for building the Signet node. These components
 implement core node functionality, but are potentially independently useful.