Move access instructions onto their own settings pages

The REST and MCP "How to access" walkthroughs now live on two dedicated
sub-pages rather than filling the top of the settings tab. The main page
keeps the at-a-glance essentials: a server status table showing whether
the HTTPS/HTTP servers are enabled alongside their URLs (now copyable),
and the API key as a standard setting row with the copy-button treatment.

The two URL tables and the MCP endpoint table previously duplicated
nearly identical rendering; they now share a single renderServerUrlTable
helper. That unification also means the MCP table now lists
subjectAltName-derived endpoints, which it previously omitted. Disabled-
row tooltips no longer say the enable switches are in "'Settings' below",
which stopped being true for content living on a sub-page; each table now
receives a location hint appropriate to where it renders. The in-content
section headings were dropped because a page's name doubles as its title,
and the top-of-tab plugin-name heading was dropped along with them, in
line with Obsidian's guidance against plugin-name headings in settings.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>