improve clarity

[Vikt0rPavlik]

Changes:

• "alphabets" -> "letters" (correct term for alphabet characters)
• "which can use it" -> "that can use it" (proper restrictive clause)
• "Hubble emit events" -> "Hubble emits events" (subject-verb agreement)
• "keeps event around" -> "keeps events around" (plural form needed)
• "fid was registers/transferred" -> "fid was registered/transferred" (correct past participle)

These changes improve documentation readability and grammatical correctness while maintaining technical accuracy.

[vercel]

@Vikt0rPavlik is attempting to deploy a commit to the farcaster Team on Vercel.

A member of the Team first needs to authorize it.