Rework cache for M3U playlist handler and adds SAFE_LOGS for easier bug reports

[sonroyaalmerol]

Context

• Hopefully addresses long export time when the db is big #100
• Adds SAFE_LOGS which redacts all URLs from the logs.

Choices

• Adds BASE_URL env var to set the M3U streams base url. Will be required for CACHE_ON_SYNC due to the HTTP request URL being unavailable if cache rebuild is done in the background.

Test instructions

Checklist before requesting a review

• I have performed a self-review of my code
• I've added documentation about this change to the README.
• I've not introduced breaking changes.

[sonroyaalmerol]

/publish

[github-actions]

The Docker image for this pull request has been built and pushed to GHCR.

Image URL: ghcr.io/sonroyaalmerol/m3u-stream-merger-proxy:pr-124