Restore Markdown link hover underline and spacing after code blocks on web (#7276)

* fix(markdown): restore link hover underline and code block spacing on web

The web renderer swap dropped both. Links: the library styles anchors
inline with text-decoration: none, so the link renderer has to track hover
itself; a stylesheet :hover rule cannot win. Spacing: the patched
renderers.codeBlock override returned the custom block bare, so it lost
the library's codeBlock margins and whatever followed sat flush against
it. The override now keeps those margins, including the zeroed trailing
margin of the last block, so web and native share one spacing config.

* test(desktop): expect Find to return focus to the chat viewport

#7263 moved focus on closing Find from the no-drag focus scope to the
scroll viewport so Page Up and Page Down keep working. The viewport emits
no window region by design (#5233), so the old assertion that the focused
element is no-drag failed on every run. Assert the new focus target and
re-check that the titlebar still has no drag exclusions.

docs/markdown-renderer.md

@@ -18,7 +18,7 @@ Math and video are disabled. Task lists and admonitions are enabled; task checkb
 
 Mermaid fences use the existing isolated diagram runtime and fullscreen viewer. Web dispatches them through the library’s code-block override. Native has no block-renderer hook, so the renderer extracts only Mermaid fences and places the existing WebView host between library-rendered segments. This is the only block exception; see [native selection limitations](native-text-selection.md) for diagram grouping and leading inline images. Streaming keeps the last valid diagram visible while the next revision renders.
 
-Native code blocks use the library's copy control and compiled grammars. Web code blocks use `HighlightedCodeBlock` through the library's `renderers.codeBlock` override. The patch also preserves web list numbering and link titles, marks pending parses with `aria-busy` so Find waits for rendered text, and carries link syntax through native and web tap events. Web inline code inside a link inherits only the link colour; its code font, size and background stay intact. Keep link variants colour-only: native pills replace text runs and prevent paths from wrapping; Android pills also use the surrounding block’s font size. The package patch is tracked by [upstream PR #997](https://github.com/software-mansion/enriched-markdown/pull/997); remove the patch when the pinned release includes it.
+Native code blocks use the library's copy control and compiled grammars. Web code blocks use `HighlightedCodeBlock` through the library's `renderers.codeBlock` override. The patch also keeps the library's block spacing around the web code block override, preserves web list numbering and link titles, marks pending parses with `aria-busy` so Find waits for rendered text, and carries link syntax through native and web tap events. Web inline code inside a link inherits only the link colour; its code font, size and background stay intact. Keep link variants colour-only: native pills replace text runs and prevent paths from wrapping; Android pills also use the surrounding block’s font size. The package patch is tracked by [upstream PR #997](https://github.com/software-mansion/enriched-markdown/pull/997); remove the patch when the pinned release includes it.
 
 The package patch also keeps overflowing native horizontal blocks in control of their drags: Android claims parent interception at touch-down and releases it for vertical drags so the chat list can scroll; iOS keeps its scroll recognizer active for outward drags at the leading edge. This prevents compact sidebar pans from taking block scrolling without changing sidebar swipes on prose or non-overflowing blocks. Native changes require a client rebuild.