Add CLAUDE.md with Conductor compatibility docs

Port documentation from react_on_rails#2301 explaining how to use
bin/conductor-exec wrapper for version manager compatibility.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: justin808

CLAUDE.md

@@ -0,0 +1,55 @@
+# React Webpack Rails Tutorial - Development Guide
+
+## Build and Test Commands
+
+```bash
+# Run development server
+bin/dev
+
+# Run tests
+bundle exec rspec
+
+# Run linting
+bundle exec rubocop
+
+# Auto-fix linting issues
+bundle exec rubocop -a
+```
+
+## Conductor Compatibility (Version Managers)
+
+### Problem
+
+Conductor runs commands in a non-interactive shell that doesn't source `.zshrc`. This means version manager shell hooks (like mise's PATH reordering based on `.tool-versions`) never run. Commands will use system Ruby/Node instead of project-specified versions.
+
+**Symptoms:**
+- `ruby --version` returns system Ruby (e.g., 2.6.10) instead of project Ruby (e.g., 3.4.3)
+- Pre-commit hooks fail with wrong tool versions
+- `bundle` commands fail due to incompatible Ruby versions
+- Node/pnpm commands use wrong Node version
+
+### Solution
+
+Use the `bin/conductor-exec` wrapper to ensure commands run with correct tool versions:
+
+```bash
+# Instead of:
+ruby --version
+bundle exec rubocop
+pnpm install
+git commit -m "message"
+
+# Use:
+bin/conductor-exec ruby --version
+bin/conductor-exec bundle exec rubocop
+bin/conductor-exec pnpm install
+bin/conductor-exec git commit -m "message"  # Pre-commit hooks work correctly
+```
+
+The wrapper:
+- Uses `mise exec` when mise is available
+- Falls back to direct execution for non-mise users (asdf, rbenv, nvm, nodenv)
+
+### Reference
+
+See [react_on_rails-demos#105](https://github.com/shakacode/react_on_rails-demos/issues/105) for detailed problem analysis and solution development.