Async Pack Scan

Commits in Beta 0.2.5:

• chore: update to 1.21

Commits in Beta 0.2.4:

• chore: update to 1.20.5

Commits in Beta 0.2.3:

• fix: manually filter packs hidden via fabric api
• chore: annotate private things in mixins as @Unique

Commits in Beta 0.2.2:

• chore: update to 1.20.4

Commits in Beta 0.2.1:

• chore: update to 1.20.2

Commits in Beta 0.2.0:

• Better synchronization

Commits in Beta 0.1.0:

• Initial commit
• Set up publish