The integration tests self-skip unless Redis answers on 127.0.0.1:6379, so CI
never ran them. A redis:7 service container with a redis-cli ping health check
now backs the job.

Adds laravel/pint and phpstan/phpstan with larastan at level 8, plus lint and
analyse composer scripts and the matching CI steps. testbench.yaml keeps the
Fledge Fiber providers out of package discovery so larastan can boot a stock
Laravel application for analysis.