Games library: identify ROMs via CRC32/DAT for accurate titles + metadata

Follow-up to the new games database (include/raylib-libretro-games.h).

Today a game's title is derived from its filename (extension stripped). Improve this with real identification.

Proposal

• Compute a hash (CRC32, and/or MD5/SHA1) per ROM during indexing; store it in the games table (add a crc32/hash column).
• Match against No-Intro / Redump DAT files to resolve the canonical game name, region, version, and (where available) year/publisher/genre; store these as columns and show them in the Games list / a details pane.
• As a cheap interim step (no DATs), clean up display titles by stripping No-Intro tags like (USA), (Europe), [!], (Rev 1) for display while keeping the raw filename.
• Hashing GBs of ROMs is expensive: do it incrementally on the scan thread, cache by size+mtime (reuse the existing "unchanged row" fast path), and make full hashing optional/deferred.

Notes

• Foundation for box-art matching #(thumbnails) and better sorting/search.
• Roadmap: TASKS.md "CRC32-based ROM identification against No-Intro / Redump dat files" and "Game metadata display in library".

Start with include/raylib-libretro-games.h and the TASKS.md entries for CRC32-based ROM identification and game metadata display. Trace the games-table indexing path, including the unchanged-row fast path, and the Games list or details pane before choosing a scoped milestone. Done should include a defined identification or title-cleanup behavior, preserved raw filenames, and matching library display and stored metadata.