Remove unnecessary FQDN in generated proxy trait adoption

[lisachenko]

Summary

• Use short (unqualified) trait names in generated proxies when the trait and proxy share the same namespace
• Keep FQCN when namespaces differ, so cross-namespace trait adoption works correctly
• Make TraitGenerator consistently wrap cross-namespace names in Name\FullyQualified (was using plain Name)

Before

class CacheableDemo implements \Go\Aop\Proxy
{
    use \Demo\Example\CacheableDemo__AopProxied {
        \Demo\Example\CacheableDemo__AopProxied::getReport as private __aop__getReport;
    }

After

class CacheableDemo implements \Go\Aop\Proxy
{
    use CacheableDemo__AopProxied {
        CacheableDemo__AopProxied::getReport as private __aop__getReport;
    }

Files changed

• src/Proxy/ClassProxyGenerator.php — namespace-aware short name for class proxy
• src/Proxy/EnumProxyGenerator.php — same for enum proxy
• src/Proxy/TraitProxyGenerator.php — same for trait proxy
• src/Proxy/Generator/TraitGenerator.php — wrap cross-namespace names in FullyQualified
• 5 test fixture files — updated expected proxy output
• 3 test files — 6 new tests covering same/different namespace scenarios

Closes #572

Test plan

• Full suite: 2477 tests, 0 failures
• 6 new tests: short name when same namespace, FQCN when different namespace (×3 generators)

🤖 Generated with Claude Code