chore: commit pending ZXDB explorer changes prior to index perf work

Context
- Housekeeping commit to capture all current ZXDB Explorer work before index-page performance optimizations.

Includes
- Server-rendered entry detail page with ISR and parallelized DB queries.
- Node runtime for ZXDB API routes and params validation updates for Next 15.
- ZXDB repository extensions (facets, label queries, category queries).
- Cross-linking and Link-based prefetch across ZXDB UI.
- Cache headers on low-churn list APIs.

Notes
- Follow-up commit will focus specifically on speeding up index pages via SSR initial data and ISR.

Signed-off-by: Junie@lucy.xalior.com

AGENTS.md

@@ -115,7 +115,8 @@ Comment what the code does, not what the agent has done. The documentation's pur
   - Do not create new branches
 - git commits:
   - Create COMMIT_EDITMSG file, await any user edits, then commit using that 
-    commit note, and then delete the COMMIT_EDITMSG file.
+    commit note, and then delete the COMMIT_EDITMSG file. Remember to keep
+    the first line as the subject <50char
 - git commit messages:
   - Use imperative mood (e.g., "Add feature X", "Fix bug Y").
   - Include relevant issue numbers if applicable.