Feature request: Static array types with fetch_types false

The fetch_types: false option breaks the serializing/parsing of array types. As an example, the following fails:

import postgres from 'postgres'

const sql = postgres({
  fetch_types: false
})

const result = await sql`SELECT * FROM unnest(${['foo', 'bar']}::TEXT[])`
// Throws: `PostgresError: malformed array literal: "foo,bar"`

It would be nice to have the option to pass static typeOID -> arrayTypeOID mappings in the options to have that work without incurring the cost of fetching the OIDs from the database.

An automatic fallback with standard type OIDs could also be an option with fetch_types: false considering these appear to be stable?

Start by running the supplied fetch_types: false example and tracing the array serialization/parsing path. Investigate how typeOID and arrayTypeOID information is obtained, then define coverage for the requested static mapping or standard-OID fallback. Done means the example works without fetching types and the behavior is tested.