[ma-04]

Why

The scheduled/push `Build, Test, and Push Docker images` run on `main` failed on 2026-10-16 with:

```
build-php (8.1): No releases available for package "pecl.php.net/apcu"
```

This was a transient PECL error, not a code problem. The same unchanged code passed on the fork (see below), and the failure didn't come from the Dockerfile.

The real amplifier is the matrix strategy. `build-php` uses the default `fail-fast: true`, so the first job to error cancels every other PHP version. In the 2026-10-16 run, 6 of 7 PHP builds were cancelled, not failed. One flaky job blocked six healthy image builds from pushing.

Change

Set `fail-fast: false` on the `build-php` matrix in `test.yml` and `deploy.yml`. Each PHP version now builds and pushes independently. The push steps already gate on `if: success()` for their own job, so a failed version still won't push.

Testing

• Baseline: `Run tests on Docker images` dispatched on the fork at the unchanged upstream `main` (ma-04/flywp-dockerfiles run 39401733427): all 12 jobs passed, including `build-php (8.1)`.
• With this change (run 39402694400): all 12 jobs passed.

Not covered

• `test.yml` is amd64-only. The multi-arch arm64 push in `deploy.yml` (where the relay `IPE_SKIP_CHECK` path from fix: install relay after imagick and skip its load check on arm64 #38 applies) has not run in CI since fix: install relay after imagick and skip its load check on arm64 #38 merged. The 2026-10-16 run failed before that step.
• The `install-php-extensions` installer is still fetched from `releases/latest`. Pinning it would prevent silent changes but needs a version bump process, so it's left for a separate decision.