[Feature] Debug/Verbose mode

[zvictor]

Debugging and understanding what is happening inside tiktok-scraper can be very difficult as it can feel very opaque.
This PR introduces the --verbose option (alternatively, the env var DEBUG=*) to allow for a more transparent operation.

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Depends on / Blocked by / Continuation of:

• propagate errors inside forEachLimit #645
• Improved error messages #646
• fix collection of posts with matching count #647
• fix since in collectPosts #658
• [Feature] Throttle requests to TikTok #659
• [Feature] retry failing request before giving up #666
• Update Readme file #667

[zvictor]

As you can see, it is becoming increasingly harder for me to separate my contributions in separated PRs.
Too many conflicts arise when I try to cherry-pick them in independent branches.

Please consider merging my previous PRs ASAP so I can continue pushing contributions.