Fix entry heading anchors on page bundles

The heading id came from .File.TranslationBaseName, which is "index"
for every leaf bundle. Since audio versions require an entry to be a
bundle, every entry with audio got the same meaningless anchor, and
pages built by a content adapter would have taken the name of the
directory holding the adapter.

Derive the id from the page's own URL instead. Single file entries keep
the anchors they already had, and bundles, adapter built pages and
custom slugs now each get their own.

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

0 files changed, 0 insertions, 0 deletions