Use byte offsets for Bluesky's hashtag facets

Add hashtag facets to Bluesky silo

Bluesky silo now tries to create link card embeds

Add debug logging for what gets flagged as microposts

Add more options for dynamic feed DOM manipulation

Fix Bluesky formatting for posts too long, or with a link

Fix upload of attached photos to Facebook Pages posts

Fix bugs with text formatting

- Fix measuring of article URLs and bulleted/ordered lists
- Fix percent-escaping of link texts

Fix typo in log message

Don't resize images when running with --dry-run

Upgrade bluesky silo to atproto 0.0.35 and unit tests.

Fixes for url flatteners

Resize photos below a file size threshold for all silos

Before we were doing it only for Bluesky, but now it's available to
all other silos.

Only process silos that did not throw an exception in pre-process.

Add utility command to forget parts of the cache.

Fix wrong help message.

Fix Bluesky unit tests

Upgrade webmention silo to new API

Fix another unit test to be more explicit about where the feed is.

Add profile URL handlers

Silos register these handlers so that everybody knows if a hyperlink is
a mention to another user on a particular social network. If any handler
matches, silos not related to that social media will skip that link.

It's possible than in rare cases we want that link everywhere, but so
far I haven't needed it, compared to all the times I didn't want these
links.