Update README makefile commands for corporate macs

[ems-sato]

Motivation and Context

Homebrew is no longer available on Corporate MacBooks, so the README's local setup instructions no longer work. This reworks them to use Miniconda + conda-forge for packages and Podman as the container runtime, replacing brew, pyenv, nvm and Colima.

Two things surfaced while testing on a clean environment:

• Port 5002 is occupied by Cisco Secure Client (csc_swgag) on corporate machines, so the AJV validator can't bind to it
• .development.env was never loaded by the app. api.py builds the AJV URL from AJV_VALIDATOR_SCHEME/HOST/PORT with no defaults, and nothing called load_dotenv(), so all three resolved to None and /validate returned 503

What has changed

• AJV validator port 5002 → 5005 across .development.env, ajv/app.js, Dockerfile, Dockerfile-ajv, .github/workflows/pull_request.yml and the README.
• Added environment.yml pinning python=3.14.6, nodejs=22.13.0, poetry=2.4.2.
• Added python-dotenv and a load_dotenv() call in api.py.
• README: conda setup section, and a temporary note on upgrading npm (see below).

Poetry is pinned to 2.4.2 rather than 2.1.2: poetry 2.1.2 requires dulwich >=0.22.6,<0.23.0 and no build in that range supports Python 3.14, so the conda solve fails.

Node is pinned to 22.13.0 because conda-forge has no 22.15.0 build (matching .nvmrc). That version bundles npm 10.9.2, on which make run never reaches poetry run python api.py and npm run start holds the terminal despite the trailing &. The README documents upgrading to npm 11.6.1 as a temporary step; this can be removed once conda-forge ships a Node build with npm 11.

How to test?

Retrace the new README steps on a corporate Macbook and confirm the setup works from a clean start

Links

Jira Ticket: https://officefornationalstatistics.atlassian.net/browse/EQS-1149