fix: correct typos, grammar errors, and formatting issues across project

[wnqqnw19]

Fixed multiple typos, grammar errors, and formatting issues found during project analysis:

1. Fixed grammar error in python/README.md (line 132): Changed "They is" to "They are"   for proper subject-verb agreement.
2. Fixed typo in antom-payment README.md (line 3): Corrected "payemnts" to "payments". 
3. Fixed capitalization in antom-payment README.md (line 9): Changed "it enhances" to  "It enhances" for proper sentence capitalization.
4. Fixed typo in antom-payment README.md path reference (line 59): Corrected "antom-payemnt-agent" to "antom-payment-agent" in the .env file path.
5. Fixed Chinese period character in agent.py (line 11): Replaced Chinese period "。" with standard period "." in the description string.
6. Added missing periods in agent.py instruction string (lines 15-16): Added proper    punctuation at the end of sentences for better readability and grammar.
7. Fixed incomplete description in pyproject.toml (line 4): Changed "That integrates..." to "An agent that integrates..." for grammatically correct and complete description.

All changes maintain code functionality while improving code quality, documentation readability, and adherence to English language conventions.

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[wnqqnw19]

I've resolved it, thanks