Nav, the home portal grid, and the library have linked both URLs since
the portals were added, but no rule generated either index — confirmed
404s in production (AUDIT §2.1). Both rules mirror the essays index;
fiction renders an empty list until content exists.
sectionOwnedTopLevelTags now lists every namespace owning a
<name>/index.html route, not just photography — Hakyll silently
overwrites on duplicate routes, so an essay tagged e.g. "music" would
have clobbered a real section landing (AUDIT §2.2).
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>