## Summary This PR renames `AnyStringKind` to `AnyStringFlags` and `AnyStringFlags` to `AnyStringFlagsInner`. The main motivation is to have consistent usage of "kind" and "flags". For each string kind, it's "flags" like `StringLiteralFlags`, `BytesLiteralFlags`, and `FStringFlags` but it was `AnyStringKind` for the "any" variant.