fix: critical boolean compatibility for PostgreSQL/SQLite

Fixed boolean value handling differences between databases:
- SQLite stores booleans as 0/1, PostgreSQL as true/false
- Add formatBoolean() calls to critical queries that were failing

Files fixed:
- adminEvents.js: Fixed status filters and archive queries
- adminDashboard.js: Fixed active/archived event counts
- expirationChecker.js: Fixed expiration checking queries
- dbCompat.js: Updated to avoid circular dependency

Added migration 024 to:
- Enable foreign keys for SQLite (PRAGMA foreign_keys = ON)
- Document boolean compatibility requirements

This fixes queries returning 0 results in SQLite when checking
boolean columns like is_active, is_archived. Critical for
proper event management and expiration handling.

Note: 23 more boolean comparisons remain to be fixed in other files.

backend/migrations/024_fix_boolean_compatibility.js

@@ -0,0 +1,29 @@
+/**
+ * Fix boolean compatibility issues between PostgreSQL and SQLite
+ * This migration updates the database configuration and existing data
+ */
+
+exports.up = async function(knex) {
+  const isPostgres = knex.client.config.client === 'pg';
+  
+  if (!isPostgres) {
+    // Enable foreign keys for SQLite
+    await knex.raw('PRAGMA foreign_keys = ON');
+    
+    // Note: SQLite stores booleans as 0/1
+    // No data migration needed as Knex handles this automatically
+    // But queries must use formatBoolean() helper
+    
+    console.log('SQLite boolean compatibility check:');
+    console.log('- SQLite stores booleans as 0/1');
+    console.log('- All boolean comparisons should use formatBoolean() helper');
+    console.log('- Foreign keys enabled');
+  }
+  
+  return Promise.resolve();
+};
+
+exports.down = async function(knex) {
+  // No rollback needed
+  return Promise.resolve();
+};