4x-VESRGAN-G: replace the blocked Mega link with the author's Google Drive file (byte-identical)

[nuri-yoo]

The only link for 4x-VESRGAN-G is a Mega file that Mega itself refuses to serve: the g API call returns EBLOCKED (checked 2026-09-11 with megatools; the web page shows the same "unavailable" state). The record's sha256/size were never in doubt, only the host.

The author's own pretrained-model list (victorca25/traiNNer docs/pretrained.md, row "SOFVESRGAN") points at a Google Drive folder named VESRGAN whose single model file is VESRGAN_G.pth — the same original filename this database records for the entry. Downloaded today, it is byte-identical to the record: sha256 3980a2e9ed6895c14a6d6379debe395e412dd9599fd53d951ea7c69d3ac14c0d, 69,026,745 bytes. As a cross-check, the sibling folder SOFVSR from the same table holds video_G.pth, which hashes to exactly 4x-video-G's recorded value, so these folders are the origin of both entries.

This replaces the dead Mega URL with a direct link to that Drive file (file/d/<id>/view?usp=sharing, the form most entries here use), following what #517 did for 4x-Remacri. sha256/size are unchanged. npm run validate-db and npm test pass locally.