Error tests, FK violations fix

- ErrorHandler tests: 77 assertions covering FK extraction, normalization, dedup, edge cases. Fix FK table map for child tables.
- Fix FK violation: (int)null → 0 in createThesis for orientation/ap/finality/license FK columns. Add FK value logging to updateThesis.
- Add CURRENT_ISSUES.md with summary of FK violation, dev debugging, and tag dedup status for next conversation

app/src/Controllers/TfeController.php

@@ -39,6 +39,7 @@ class TfeController
     public static function create(): self
     {
         require_once APP_ROOT . '/src/Database.php';
+        require_once APP_ROOT . '/src/ErrorHandler.php';
 
         return new self(Database::getInstance());
     }
@@ -64,7 +65,7 @@ class TfeController
         try {
             $data = $this->db->getThesisById($thesisId);
         } catch (Exception $e) {
-            error_log('TfeController: ' . $e->getMessage());
+            ErrorHandler::log('tfe_view', $e, ['thesis_id' => $thesisId]);
             $this->redirectHome();
         }