Reads packwiz pack (pack.toml + index.toml + per-file .pw.toml) and
emits a simple-mod-sync sync_version=3 manifest. Drops server-only
mods, skips CurseForge metadata-mode entries with a warning, maps
content type from the parent directory of each metafile.
Optional --bundle-non-mods zips config/, options.txt etc into one
archive served as a 'packed' entry — covers the gap where simple-mod-sync
only ships zip-extractable content for non-mods.
15 tests, includes integration against upstream packwiz-example-pack.
