Replace Node.js 20 with Node.js 22

[dcroote]

Node.js 20 security support ends in 6mo (30 Apr 2026) and using Node.js 20 is currently blocking #2031 (see #2033 (comment)).

Previous upgrade Node.js 18 -> 20 upgrade PR for reference: #1920.

This will require terraform, aws, and gcp upgrades.

@google-cloud/functions-framework needs to be updated to 4.0.0

NEVER USE THE ANY TYPE

The following 3 commands must pass before committing:

yarn run bootstrap
yarn run build
yarn run lint