feat(ci): add test coverage visibility to CI pipeline (Stage 4D)
Enhance flutter-test.yml to run tests with --coverage and parse lcov.info
files, producing aggregate summary table with per-package line coverage.
Changes:
- flutter-test.yml: add --coverage flag, lcov.info parsing, coverage %
- collect_coverage.sh: new local coverage helper with summary table
- tools/README.md: document collect_coverage.sh script
- .gitignore: add coverage/ directories
- master_development_brief.md: mark Stage 4D complete, document baseline
coverage table, update next branch to Stage 5A, resolve improvement #5
Baseline coverage (2026-05-22):
- core: 85.7%% (42/49 lines, 20 tests)
- design_system: 100.0%% (88/88 lines, 41 tests)
- feature_wordpress: 84.7%% (857/1012 lines, 294 tests)
- kell_web: 54.1%% (191/353 lines, 24 tests)
- Overall: 78.4%% (1178/1502 lines, 379 tests)
No minimum thresholds enforced — visibility first.