Final tasks for 0.0.8

[PgBiel]

• [x] Backport #111 and #116 to 0.0.x
• [x] Ensure the new changes and fixes look fine the typst-test.pdf output for Typst 0.2.0
• [x] Check the same for unreleased Typst 0.11.0 (main branch)
• [x] Add docs for fit-spans (#111)
• [x] Write changelog
• [x] Open PR in https://github.com/typst/packages (https://github.com/typst/packages/pull/339)