v0.1.2

Fixes the app store rejecting the app with "Failed to parse contents of tildagon.toml".

The cause was a UTF-8 byte order mark written to the front of the file by a Windows editor; a strict TOML parser treats it as a syntax error. tildagon.toml, app.py and adsb.py all carried one, and all three are now written as UTF-8 without a BOM.

Nothing in the app itself had noticed — Python skips a BOM in source and every editor renders the file identically — so there is now a packaging test asserting that no repo file starts with a BOM, that tildagon.toml parses, and that its category, string version, description length and author length all match the store's schema.

No functional changes to the app.