Add TweetClaw export converter

[kriptoburak]

Summary

• Add a stdlib converter from TweetClaw CSV, JSON, JSONL, or NDJSON exports to the existing project_twitter_data.csv format.
• Preserve the original sentiment script and its tweet_text, retweet_count, reply_count input shape.
• Document how to generate a replacement input file from an export before running FinalProject.py.

Validation

• python3 -m py_compile tweetclaw_to_project_data.py
• Sample TweetClaw CSV conversion produced 2 rows and defaulted missing counts to 0.
• git diff --check