MTG farm volunteer client v21

Superseded by client-v22, which adds the 2.0.14+6747f05e908 engine row (the dead-card batch). This asset stays downloadable and the digest below remains true for it.

One-zip Windows volunteer client for the MTG sim farm. Unzip, double-click run-client.bat, enter the farm URL and your runner credential on the first-run page, click Add, pick your work, and go.

New in v21: the bundle is GPLv3. LICENSE (the verbatim GNU General Public License v3.0) travels in the zip, and NOTICE.txt now says what is under it: the bundle's own code (copyright 2026 fuzzy1450), Forge (downloaded on demand, GPLv3 as ever), the harness classes the farm hands out -- built from Harness.java, which the farm now serves from the same place, GET /api/farm/harness/source -- and the embedded Python's PSF license. Nothing about how the client plays changed.

From v20: a stopped worker starts from its own row. From v19: a candidate's own named derived card order. From v17: the 2.0.14+139b268b780 engine row. From v16: workers persist -- add, start, stop and delete are separate, and rows and their game counts survive a restart. From v12: the client updates itself.

Headless: farmrunner.py --mode backfill --decks REF[,REF...] [--scope within].

Ships Windows embeddable Python 3.12.10; the Forge engine (~205 MB) is downloaded on demand. Needs a farm that advertises active_engine on /hello (any farm since de63260).

sha256(mtg-farm-client-v21.zip) = b01b18c9e41d80f3c7d6fddf4fb1bc8d8fdb8cdfec7ab517efa47ce9dc635659