Fix a bug where a custom block could not be placed directly after a list.

Improve error handling in renderer.py.

• Support custom marks with render_text method
• If a block content has multiple custom marks defined, only the first one will be applied

Add a new render_text method to MarkerDefinition.
The motivation behind adding it is to give a library user more flexibility when they want to render a portable text block, for example:

• a text block is supposed to be rendered under a certain condition
• a content inside a text block is a placeholder

Support user-defined custom marks

Fixed a bug, where user defined custom marks weren't registered by the renderer correctly.

Package re-release under new name.

The package was renamed from sanity-html to portabletext-html, so the naming is more in line with other portable text-related tools and packages.

Removes streamhandler and debug log-level configuration. This way logging can be configured downstream, and can be opted into rather than opted out of.

Ensure that the publishing workflow works after renaming package from python-sanity-html to sanity-html

Test release