[feat]: Rename `<pf-tile>` to `<pf-v5-tile>`

[bennypowers]

Summary

Rename <pf-tile> to <pf-v5-tile> and update associated CSS custom properties to use the pf-v5 prefix.

Scope

• Rename element tag from pf-tile to pf-v5-tile
• Rename all CSS custom properties (e.g. --pf-tile--* to --pf-v5-tile--*)
• Update internal class names, imports, and type declarations

Requirements

• MUST maintain feature parity with the current <pf-tile> implementation
• MUST rename all public CSS custom properties
• MUST update HTMLElementTagNameMap declarations
• SHOULD provide a codemod or migration guide for downstream consumers