Fix: Use chokidar for consistent glob pattern matching in build mode

[reebalazs]

Fixes #21

Problem

Build mode silently processes zero files when using extglob patterns like (src|__tests__) in srcDir, while watch mode works correctly with the same pattern.

Root Cause

The CLI used two different glob libraries with incompatible pattern support:

| Mode | Library | (src|__tests__) interpretation |
|------|---------|----------------------------------|
| Build | globSync from glob | Literal string (finds nothing) |
| Watch | chokidar (uses picomatch) | Extglob "OR" pattern (works) |

This caused confusing behavior where --watch would find and process files, but running without --watch would silently succeed with no output.

Example

{
  "srcDir": "./(src|__tests__)/**/*"
}

• ✅ pgtyped-rescript -c config.json --watch → finds files in both src/ and __tests__/
• ❌ pgtyped-rescript -c config.json → finds 0 files, exits silently

Solution

Use chokidar for file matching in both modes. This ensures consistent glob pattern interpretation regardless of whether watch mode is enabled.

Changes

1. Replaced globSync with chokidar-based getMatchedFiles in packages/cli/src/index.ts

   • Added async getMatchedFiles() function that uses chokidar with persistent: false
   • Removed glob package dependency for file matching

2. Added comprehensive tests in packages/cli/src/glob.rescript.test.ts

   • Tests for simple srcDir patterns
   • Tests for extglob (src|__tests__) syntax
   • Tests for brace expansion {src,__tests__} syntax
   • Tests for embedded wildcards
   • Tests for empty directory handling

Test plan

• All existing tests pass
• New glob pattern tests pass (5 tests)
• Manual test: verify build mode works with extglob patterns