Add missing jira_tickets sync columns migration and improve error messages

- Add add_jira_sync_columns_pg.js migration (jira_id, jira_status, last_synced_at, created_by)
- Register in run-all.js before the flexible creation migration
- Replace all generic 'Internal server error' with actual err.message in jiraTickets routes
- Users and admins can now see the real failure reason instead of a useless generic message

backend/migrations/add_flexible_jira_ticket_creation.js

@@ -28,6 +28,23 @@ async function run() {
     await pool.query(`ALTER TABLE jira_tickets ALTER COLUMN vendor DROP NOT NULL`);
     console.log('✓ vendor NOT NULL constraint dropped (or was already nullable)');
 
+    // Add jira_id, jira_status, last_synced_at, created_by columns
+    // (originally from SQLite migration add_jira_sync_columns.js — never ported to Postgres run-all)
+    await pool.query(`ALTER TABLE jira_tickets ADD COLUMN IF NOT EXISTS jira_id TEXT`);
+    console.log('✓ jira_id column added (or already exists)');
+
+    await pool.query(`ALTER TABLE jira_tickets ADD COLUMN IF NOT EXISTS jira_status TEXT`);
+    console.log('✓ jira_status column added (or already exists)');
+
+    await pool.query(`ALTER TABLE jira_tickets ADD COLUMN IF NOT EXISTS last_synced_at TIMESTAMPTZ`);
+    console.log('✓ last_synced_at column added (or already exists)');
+
+    await pool.query(`ALTER TABLE jira_tickets ADD COLUMN IF NOT EXISTS created_by INTEGER`);
+    console.log('✓ created_by column added (or already exists)');
+
+    await pool.query(`CREATE INDEX IF NOT EXISTS idx_jira_tickets_jira_id ON jira_tickets(jira_id)`);
+    console.log('✓ jira_id index created (or already exists)');
+
     // Add source_context column with default value (IF NOT EXISTS makes it idempotent)
     await pool.query(`
         ALTER TABLE jira_tickets