fix: .versionrc.json postbump references non-existent sync-native-versions.js

[carlos-alm]

Problem

.versionrc.json has a postbump script that references sync-native-versions.js:

"scripts": {
  "postbump": "node scripts/sync-native-versions.js"
}

But the file only exists as scripts/sync-native-versions.ts. The .js variant does not exist.

Impact

Currently low impact because the npm version lifecycle hook in package.json correctly runs the .ts version via node-ts.js wrapper:

"version": "node scripts/node-ts.js scripts/sync-native-versions.ts && git add package.json crates/codegraph-core/Cargo.toml"

The .versionrc.json postbump is both redundant (npm lifecycle already handles the sync) and broken (references a non-existent .js file). If commit-and-tag-version ever changes execution order or the npm lifecycle hook is removed, the version sync would silently fail.

Fix

Either:

1. Remove the postbump from .versionrc.json since the npm version lifecycle already handles it, or
2. Update it to node scripts/node-ts.js scripts/sync-native-versions.ts

Found during review of #822.