Add namespace qualifier highlighting

[alfredomtx]

Summary

Dims namespace qualifiers in inline FQNs using @label capture, matching IDE behavior like PhpStorm.

Before: \App\Models\User - all same color
After: \App\Models\ - dimmed, User - highlighted

Changes

Targets specific expression contexts where inline FQNs appear:

• Class constant access: \App\Models\Foo::CONST
• Static method calls: \App\Models\Foo::method()
• Object creation: new \App\Models\Foo()
• Type annotations

use statements are NOT affected.

Theme Configuration

"theme_overrides": {
  "One Light": {
    "syntax": {
      "label": { "color": "#a0a1a7" }
    }
  }
}

Example: