Optimize prepare_inherited_attributes() and support helpers

[hamdyelbatal122]

Description

This PR optimizes prepare_inherited_attributes() and support helpers (locale_has_pluralization(), get_model_label(), is_app_url()) by removing unnecessary Collection and Stringable object allocations in favor of native PHP iteration and memoization.

Changes

• Refactored prepare_inherited_attributes() from a collect() / str() pipeline to a single-pass foreach loop with str_starts_with().
• Added string typecasting to attribute keys for safe numeric key handling.
• Added static memoization for locale_has_pluralization() and get_model_label().
• Replaced str()->startsWith() with str_starts_with() in is_app_url().

Benchmark (100k iterations of prepare_inherited_attributes())

• Before: ~367ms
• After: ~62ms (~6x speedup, 83% time reduction, 0 extra object allocations)

Testing

Ran full test suite (707 passed in Support, all playground tests passing).