Trigger generator tests when TypeScript files change (#2208)

## Summary
- When TypeScript files in `packages/react-on-rails/` change, CI now
also triggers generator tests
- Generator tests perform a full build which catches TypeScript
compilation errors

## Problem (Fixes #2205)
PR #2125 changed TypeScript types in
`packages/react-on-rails/src/types/index.ts`, which exposed a latent
type error in `serverRenderReactComponent.ts`. This wasn't caught until
the release script ran `pnpm publish` which performs a fresh TypeScript
build.

The generator/example tests would have caught this because they run a
full build, but they weren't triggered because the CI change detection
didn't consider `packages/react-on-rails/**` changes as requiring
generator tests.

## Solution
Updated `script/ci-changes-detector` to trigger generator tests when
`JS_CHANGED=true` (which includes TypeScript file changes in
`packages/react-on-rails/src/`).

## Test plan
- [ ] Verify the script correctly detects TypeScript changes and sets
`run_generators=true`
- [ ] CI passes

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Claude <[email protected]>

Author: justin808

script/ci-changes-detector

@@ -267,7 +267,9 @@ if [ "$SPEC_DUMMY_CHANGED" = true ] || [ "$RUBY_CORE_CHANGED" = true ] || [ "$JS
   RUN_DUMMY_TESTS=true
 fi
 
-if [ "$GENERATORS_CHANGED" = true ]; then
+# JS changes trigger generator tests because generators do a full build
+# which catches TypeScript compilation errors (see issue #2205)
+if [ "$GENERATORS_CHANGED" = true ] || [ "$JS_CHANGED" = true ]; then
   RUN_GENERATORS=true
 fi