[rootsiemen]

Closes #1182

What changed

• servers.*.processes now has ->min(1) in ConfigurationTreeBuilder (keeps defaultNull): 0 and negative values are rejected at config validation with a clear InvalidConfigurationException instead of passing through.
• Added config tests: reject processes: 0 and processes: -1, accept the boundary 1 and the null default (one field per process() call, per FAQ-035).
• CHANGELOG entry under [Unreleased] -> Fixed.

Why

ServerWorker passes the value straight to Worker::$count, and Workerman silently clamps it to one worker — so a typo like processes: 0 produced a running server with no visible error. Failing fast at config load surfaces the mistake immediately.

SupervisorWorker's <= 0 filter was left untouched: it guards a different path (the #[AsProcess] attribute processes, not the servers.*.processes config node), so it stays as defense-in-depth for programmatic config.

Tests

• ConfigurationTreeBuilderTest (new tests first failed pre-fix, proving the bug: 0/-1 passed validation; after the fix all pass): 3/3 new tests green.
• Targeted suites with a fresh composer install: ConfigurationTreeBuilderTest + SupervisorWorkerTest 69/69 green; ServerWorkerTest 44/46 — the 2 failures (testUnreadableCertThrowsException, testUnreadableKeyThrowsException) also fail on pristine master: the suite runs as root, so chmod-000 cert/key files stay readable (pre-existing, unrelated).
• composer lint: php-cs-fixer, PHPStan level 8, Rector, kb-lint, check-changelog, exception-usage and upgrade-exceptions all OK. Two pre-existing failures unrelated to this diff: shellcheck SC2015 (info) in the shared bin/worktree-done.sh (byte-identical script, must not be edited) and hadolint not installed in this environment.