Rewriting Claw's HTML parser for over-the-air updates

NOTE I used LLMs to help debug some of the code explained below, and ended up throwing away a lot of it while re-reviewing that work as part of writing this post. People have strong opinions on the use of LLMs and I don’t want them to feel misled by discovering partway through that this work involved an LLM, so here’s your PSA. First, some background. Claw is an Android app for browsing the linkblogging community known as Lobsters. For years, the app relied on a JSON API to interact with the site. Some months ago, I came across a GitHub comment from the site admin explaining that the JSON API is considered a Ruby on Rails misfeature and not something he supports for external integrations. I don’t expect it to ever fully disappear since many other third-party integrations rely on it, but I decided I should probably look into options anyway. I filed an issue with my initial findings then pretty much forgot about it for over half a year. The problems with HTML parsing In May 2026 I…