[ci] Is dart format doing what we want (in CI)?

While working on an unrelated task, I noticed the following output in the dart format check:

```
Running Dart format...
Warning: Package resolution error when reading "analysis_options.yaml" file for "samples/client/flutter/restaurant_finder/app/lib/main.dart":
Failed to resolve package URI "package:lints/recommended.yaml" in include at "/home/runner/work/a2ui/a2ui/analysis_options.yaml".
Warning: Package resolution error when reading "analysis_options.yaml" file for "samples/client/flutter/restaurant_finder/app/lib/src/main.dart":
Failed to resolve package URI "package:lints/recommended.yaml" in include at "/home/runner/work/a2ui/a2ui/analysis_options.yaml".
Warning: Package resolution error when reading "analysis_options.yaml" file for "samples/client/flutter/restaurant_finder/app/test/widget_test.dart":
Failed to resolve package URI "package:lints/recommended.yaml" in include at "/home/runner/work/a2ui/a2ui/analysis_options.yaml".
Warning: Package resolution error when reading "analysis_options.yaml" file for "samples/client/flutter/restaurant_finder/e2e_test/test/infra_test.dart":
Failed to resolve package URI "package:lints/recommended.yaml" in include at "/home/runner/work/a2ui/a2ui/analysis_options.yaml".
Warning: Package resolution error when reading "analysis_options.yaml" file for "samples/client/flutter/restaurant_finder/e2e_test/test/test_infra/ai_client.dart":
Failed to resolve package URI "package:lints/recommended.yaml" in include at "/home/runner/work/a2ui/a2ui/analysis_options.yaml".
Formatted 13 files (0 changed) in 0.02 seconds.
```

> **Failed to resolve package URI `"package:lints/recommended.yaml"` in include at `".../analysis_options.yaml"`.**

See [this build task](https://github.com/a2ui-project/a2ui/actions/runs/33453710575/job/99689136987?pr=1935#step:7:51).

Are we applying the lints that we expect?

Look at the CI workflow that runs dart format, likely in .github/workflows/. Examine the analysis_options.yaml file at the repository root to see the include for package:lints/recommended.yaml. Check if the lints package is properly resolved in the CI environment, possibly by ensuring dependencies are fetched before formatting. Verify the formatting step still applies the intended lint rules.

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