[v1.82.0] Fulfilling more user requests

Don't have a theme planned for this one so going back to knocking off more user requests.

Changes so far:

• Fix a bug where the block instance button doesn't do anything on the instance information screen.
• Fix gesture conflicts on the image preview screen.
• Add feature that shows per-user scores in post/comment headers. Enabled by default. Can be disabled in settings.
• Improvements to duplicate post detector.
• Fix a crash due to the new PieFed comment reporting endpoints.
• Changed default for "hide banner if no banner" from off to on.
• Fixed more bugs related to the duplicate post detector.