MC1.21-0.1.0

Change set since the beginning:

43e9a10: Bump version to 0.1.0
de68cf4: Add artifact git tag test
cbb4a99: Add more github workflow trigger target
f2c20d3: Adjust mod description and license header
8050d7b: Setup github build workflow
3ed81bf: Add readme instructions
10f37f2: Constant extracting on sync toasts
fb3a8f0: Comment that options sync should be loaded on both side
9c7e105: Adjust resource pack sync toast
0881568: Fix sync manifest merging
ca8e6d8: Add source code
035b541: Add spi config and license
2afaac4: Adjust readme
0c952fd: Add build files
ed5f0e6: Initial commit