add new webxdc APIs

[r10s]

closes #2411

[hpk42]

Caspar, thanks joining the discussion from a general web-app/server angle! What is different with webxdc apps and how clicking an info message opens a href is that there is not neccessarily a "current" page as the info message might be a historic message and you have since navigated the app to a different page. So if the href is simply "#something" then the messenger would have a hard time providing the implicit full location when starting the webview. This is different with classic web-apps where a href is always used within some current page/context and resolved relative to it.

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On Mon, Nov 25, 2024 at 05:47 -0800, adb wrote: @adbenitez commented on this pull request. > + let file = if let href { + if href.starts(with: "#") { + "index.html" + href + } else { + href + } + } else { + "index.html" + } e.i. the #fragment is not relative to the current open page, otherwise the behavior would be arbitrary receiving a #fragment in the current open page when it was intended for another subpage