Replace the broken /glossary/ stub with a real hub

[LukasWallrich]

Why this needs addressing

https://forrt.org/glossary/ currently returns HTTP 200 with a 261-byte HTML stub:

• <title> is the literal URL https://forrt.org/glossary/english/.
• The canonical points to /glossary/english/ rather than the requested URL.
• Navigation relies on a meta refresh.

The individual glossary schema also uses /glossary/ as the DefinedTermSet URL, so the site is presenting a broken/stub entry point as the canonical glossary hub.

Requested change

Make /glossary/ a real, server-rendered language-selection hub with:

• a human-readable title and description;
• a self-referential canonical;
• crawlable links to the English, German, Chinese, Arabic, and Turkish editions;
• a useful H1 and accessible language labels;
• no meta-refresh dependency.

Keep existing language and term URLs stable. If a redirect is retained for any legacy path, it should be a real server-side redirect rather than a meta refresh where the hosting platform permits it.

Acceptance criteria

• /glossary/ returns a useful document with a self-canonical and no meta refresh.
• All five language roots are linked with ordinary <a href> elements.
• DefinedTermSet.url and breadcrumb generation refer to the intended hub.
• Existing term URLs and hreflang relationships continue to work.

[LukasWallrich]

Generation-pipeline clarification

The root/language glossary index pages are hand-maintained entry-point content, so the hub can be implemented there or in a dedicated Hugo layout. This issue does not call for editing generated term files; preserve the generator’s outputs and term URLs.