Merge pull request #442 from calibreapp/dependabot/npm_and_yarn/postc…

…ss-8.5.14

Bump postcss from 8.5.6 to 8.5.14

Merge pull request #353 from calibreapp/png-default-compress

😵‍💫 Alter PNG quality back to 80

Merge pull request #347 from calibreapp/avif

🖼️ Process AVIF images

Merge pull request #339 from calibreapp/pr-changed-images

✨ Only optimise new or changed images

Add link to throttling limits, improve summary text

Merge pull request #45 from steveoh/patch-1

docs: clarify the docs

Update readme

Merge pull request #2 from calibreapp/overall-metrics

Add overall metrics for processing

Update readme

Added everything