[framework-best-practices] Expand actionlint scope to include all first-party workflows

## Framework / Library Best Practices Findings

### 1. `make lint-workflows` underuses `actionlint` by manually allowlisting files
**Library:** `actionlint` v1.7.10 (declared in `Makefile`)

**Library feature:** Repository-wide workflow discovery and linting (run `actionlint` without per-file arguments, or with broad globs).

**Current code:**
- `Makefile:209-213` builds a narrow `find` allowlist:
```make
find .github/workflows -maxdepth 1 ( -name "trigger-*.yml" ... -name "ci.yml" -o -name "release.yml" -o -name "smoke-test-install.yml" )
```
- `Makefile:214-217` lints only that list:
```make
$$ACTIONLINT "$$file" || exit 1
```
- Existing workflows are therefore skipped, including:
- `.github/workflows/ci-tests.yml`
- `.github/workflows/mkdocs.yml`

**Simplification:** Replace the manual allowlist with native `actionlint` discovery so all first-party workflows are linted automatically. This removes maintenance burden and prevents silently missing newly added workflow files.

**Why it matters:** Workflow syntax/expression issues in skipped files can merge undetected until runtime, increasing CI breakage risk.

**Documentation:** https://github.com/rhysd/actionlint#usage

## Suggested Actions
- [ ] Update `lint-workflows` to run `actionlint` with repo-wide discovery (or an explicit broad glob) instead of the current hand-maintained allowlist.
- [ ] Keep any necessary exclusions explicit (for generated files) so first-party workflow files like `ci-tests.yml` and `mkdocs.yml` are always linted.

> [!WARNING]
>
> ⚠️ Firewall blocked 1 domain
>
> The following domain was blocked by the firewall during workflow execution:
>
> - `docs.astral.sh`
>
> To allow these domains, add them to the `network.allowed` list in your workflow frontmatter:
>
> ```yaml
> network:
> allowed:
> - defaults
> - "docs.astral.sh"
> ```
>
> See [Network Configuration](https://github.github.com/gh-aw/reference/network/) for more information.
>
>

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