feat: add update-checker.sh

[stasadev]

The Issue

We should have a way to determine if an add-on is outdated.

This PR depends on #75 (for README_ADDON.md upstream example).

How This PR Solves The Issue

TODOs:

• Create update-checker.sh
• Look through the existing checks, add new ones if necessary.
• Decide how to use it, maybe it should run in a separate workflow file? (An upstream file should always be used here)

Manual Testing Instructions

Run this in some add-on directory:

curl -fsSL https://raw.githubusercontent.com/ddev/ddev-addon-template/20250430_stasadev_update_checker/.github/scripts/update-checker.sh | bash

Automated Testing Overview

Release/Deployment Notes

[rfay]

I tried it out on rfay/ddev-php-patch-build and it gave me useful information:

ERROR: Actions needed:
- README.md should not contain 'project is maintained' badge, see upstream file https://github.com/ddev/ddev-addon-template/blob/main/README_ADDON.md?plain=1
- README.md should contain badge: add-on registry, see upstream file https://github.com/ddev/ddev-addon-template/blob/main/README_ADDON.md?plain=1
- README.md should contain badge: last commit, see upstream file https://github.com/ddev/ddev-addon-template/blob/main/README_ADDON.md?plain=1
- README.md should contain badge: release, see upstream file https://github.com/ddev/ddev-addon-template/blob/main/README_ADDON.md?plain=1
- install.yaml should contain 'ddev_version_constraint: ">= v1.24.3"', see upstream file https://github.com/ddev/ddev-addon-template/blob/main/install.yaml
- GitHub template missing: .github/ISSUE_TEMPLATE/bug_report.yml, see upstream file https://github.com/ddev/ddev-addon-template/blob/main/.github/ISSUE_TEMPLATE/bug_report.yml?plain=1
- GitHub template missing: .github/ISSUE_TEMPLATE/feature_request.yml, see upstream file https://github.com/ddev/ddev-addon-template/blob/main/.github/ISSUE_TEMPLATE/feature_request.yml?plain=1
- GitHub template missing: .github/PULL_REQUEST_TEMPLATE.md, see upstream file https://github.com/ddev/ddev-addon-template/blob/main/.github/PULL_REQUEST_TEMPLATE.md?plain=1

[stasadev]

TODO:

• add check for #!/bin/bash > #!/usr/bin/env bash
• check that .github/workflows/tests.yml uses ddev/github-action-add-on-test@v2

[tyler36]

This is a great idea!

I was playing around with a local addon and got:

- Remove unnecessary file: README_DEBUG.md

Wondering why we are removing debugging information. It's important this is documented somewhere, so where is ideal?

[rfay]

Wondering why we are removing debugging information. It's important this is documented somewhere, so where is ideal?

The documentation belongs in the template (or DDEV docs, or ddev.com) not in the add-on where it just gets stale rather fast.