* Lossless image optimization (using ImageOptim).
This shouldn't change the visual appearance of any images. ImageOptim
was run with the highest compression setting except that JPEG metadata
stripping was disabled because some users prefer to avoid stripping
JPEG metadata.
* Update READMEs that have Changelogs for themes impacted by lossless image optmization change.
* Update single.html template
Allow post content to stretch full width, and turn on "inner blocks use content width" option.
* Add screenshot.png
Add theme screenshot and update the image credits.
* Update post-meta.html
Update the typography of the post meta template part.
* Update search.html
Make the search result page use grid layout for posts.
* Turn post byline into a pattern.
Turn post byline into a pattern to make it translatable.
* Update post title
Update post title font size in index/archive templates.
* Update theme.json
Increase the line-height for headings.
