Fix the pre-existing broken test CI baseline (Flutter pin, gen-l10n, lint gate)

[valorengels]

Context: This is a Flutter project template for small teams using AI-assisted development. Its CI test job is red on main itself — not caused by any in-flight PR — which blocks merging every feature branch. This issue tracks fixing that broken baseline.

Problem

The template's flutter-test.yml CI test job fails on main, so no PR can merge. The failure is pre-existing and unrelated to feature work.

Current behavior:

• The CI test workflow pins Flutter 3.27.0, which resolves old dependency versions (e.g. freezed 3.0.6, analyzer 6.11.0) that fail to generate Freezed when/whenOrNull, producing analyzer errors like The method 'when' isn't defined for the type 'Result'.
• The workflow runs flutter pub run build_runner build but never flutter gen-l10n, so the generated lib/l10n/generated/app_localizations.dart is missing in CI (the files are gitignored and not generated).
• Even with both fixed, flutter analyze --fatal-infos fails on ~121 info-level lint findings across lib/ and test/ (style issues: require_trailing_commas, avoid_redundant_argument_values, avoid_implementing_value_types, etc.).

Desired outcome:

• The test job passes on main: correct Flutter/dependency versions, l10n generated, and either the lint findings resolved or the --fatal-infos policy relaxed deliberately.
• flutter test (55/55) and flutter analyze pass in CI, so feature PRs can merge.

Definitions

Term	Definition	Reference
Freezed	A Dart code-generation package that produces sealed-union .freezed.dart files (when/whenOrNull methods)	pub.dev/freezed
l10n	Localization; flutter gen-l10n generates app_localizations*.dart from .arb files	Flutter i18n

Solution Sketch

• Bump the pinned Flutter version in flutter-test.yml (and the other workflows if needed) from 3.27.0 to 3.44.8, matching the repo's documented toolchain and the rest of the ecosystem.
• Add a flutter gen-l10n step to the test workflow before flutter test (and to any build workflow that needs it).
• Resolve the lint findings (via dart fix/dart format where automatic; manually for the rest) OR relax the --fatal-infos analyzer gate if the infos are style-only — with a documented rationale.
• Update pubspec.lock to the working dependency resolution (verified: with Flutter 3.44.8, flutter test passes 55/55).

Prior Context

• The repo's README.md documents the toolchain as Flutter 3.44.8, JDK 17, AGP 9.0.1, Gradle 9.1.0 — the CI's Flutter 3.27.0 pin contradicts this.

Recon Summary

Confirmed:

• flutter-test.yml pins flutter-version: '3.27.0' and runs build_runner but not gen-l10n.
• With Flutter 3.44.8 + updated lockfile + gen-l10n, flutter test passes 55/55 and flutter analyze reports only info-level findings.
• The test check fails identically on main and on in-flight PRs docs: reconcile template docs and optional-auth story #16/fix: regenerate Android Gradle scaffolding for runnable template (fixes #13) #17 — pre-existing, not a PR regression.

Revised:

• The fix is a dependency-version + CI-config + lint-cleanup rework, not a one-line change.

Pre-requisites:

• None — this is the fix.

Dropped:

• Committing generated .freezed.dart/*.g.dart/l10n files (the repo deliberately gitignores them); the intended pattern is generating in CI.

Acceptance Criteria

• flutter-test.yml runs on Flutter 3.44.8 and includes a flutter gen-l10n step.
• The test job passes on a main branch PR (no analyzer errors, tests pass).
• flutter analyze produces no errors/warnings (infos may remain if the --fatal-infos gate is relaxed with rationale).
• Feature PRs can merge without hitting the pre-existing test failure.

Downstream

This issue feeds into /do-plan, then /do-build. It is the pre-requisite that unblocks merging the template's in-flight PRs (#16, #17) and any future work, since a red test baseline blocks the CI merge gate.