[efeesrefinal]

A pool.query() or pool.connect() waiting in the queue never settles if pool.end() is called, and end() still resolves. Once the pool is ending a released client is removed and _pulseQueue returns early, so the queue is never read. This was reported in #3819, which its author closed without a fix.

const pool = new Pool({ max: 1 })
const client = await pool.connect()
const queued = pool.query('SELECT 1') // never settles
const ended = pool.end()
client.release()

Requests queued before end() now run, in line with the existing test pool.end() - finish pending queries, and the clients are removed once the queue is empty. New checkouts during the drain are still rejected. #3750, a draft, does this too as part of reusing a pool. This is only the fix for the hang, if that helps.

Added a test to ending.js that times out without the change. On PostgreSQL 16 and Node 22 the pg-pool tests give 88 passed and 1 failed. The failure is a test that needs pg-native, which I didn't build, and it fails the same way without the change. I did not run the pg package tests.