enhance(backend): replace bcrypt with argon2

[KiTTYsh]

What

• Change password hashing algorithm from bcrypt to argon2.
• Retain login compatibility with bcrypt algorithm, and re-hash passwords that still use bcrypt during sign-on.

Why

• Increase security in the event of database compromise
• Allow passwords longer than 72 bytes, solving upstream issue パスワードの最大の長さを72バイトに制限するか鍵導出関数を変更する misskey-dev/misskey#11181
• Allow password compatibility with other forks that have already done this, such as Sharkey, Firefish, and IceShrimp

Additional info (optional)

Cherrypicked 7111c6c9 and e17dcd78 from Sharkey.

Testing performed:

• Passwords working after migrating to CherryPick from Sharkey ✅
• Passwords working for new accounts created before and after this commit ✅
• pnpm test performed with 100% success ✅
• Docker container built and run successfully ✅
• Running in production for a week on kitty.social without any issues

Checklist

• [✅] Read the contribution guide
• [✅] Test working in a local environment
• [🟧] (If needed) Update CHANGELOG_CHERRYPICK.md
• [❌] (If possible) Add tests

[noridev]

🙏🙏🙏

[Linux-Is-Best]

Awesome!

This will help and encourage people to move to CherryPick. 🥳