docs(ui): scroll the sidebar so the active (bold) link is in view on load

Deep-linking into a low doc (e.g. ratings/get_ratings from the overview
page) opened the right menus but sat the highlight below the sidebar's
visible scroll area. scrollSidebarToActive() runs at docs Alpine init:
finds the link for the current path, and if it's outside the sidebar's
scrollport, moves ONLY the sidebar's own scrollTop to clamp it into the
nearest edge — never the page scroll. Skips the off-canvas mobile
drawer. (Same behavior as Docusaurus/MkDocs on deep links.)

Live: x-init wired on docs pages, function in the shipped bundle,
make test green, 146 vitests.

templates/docs_templ.go

@@ -71,7 +71,7 @@ func DocsLayout(nav Navigation, doc Document, user User, currentPath string) tem
 		if templ_7745c5c3_Err != nil {
 			return templ_7745c5c3_Err
 		}
-		templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 4, "<body x-data=\"docs\" x-init=\"initializeSearch(); initializeCodeCopyButtons()\" class=\"")
+		templ_7745c5c3_Err = templruntime.WriteString(templ_7745c5c3_Buffer, 4, "<body x-data=\"docs\" x-init=\"scrollSidebarToActive(); initializeSearch(); initializeCodeCopyButtons()\" class=\"")
 		if templ_7745c5c3_Err != nil {
 			return templ_7745c5c3_Err
 		}