refactor: rename lib/ to core/ for clearer core-module separation

Rename the top-level lib/ directory to core/ so the project root
immediately communicates which code is core platform and which lives
in modules/. PHP namespaces (MintyPHP\*) are unchanged — only the
Composer PSR-4 path mapping moves from lib/ to core/.

Module-internal lib/ directories (modules/*/lib/) are untouched.

Updated across the full stack:
- composer.json PSR-4 mapping
- bootstrap entry points (web/index.php, bin/*, tests/bootstrap.php)
- tooling configs (phpstan.neon, phpunit.xml, php-cs-fixer)
- 26 architecture contract tests
- enforcement-policy, guard-catalog, quality-gates
- all documentation (CLAUDE.md, README, 25 docs/, .agents/skills/)
- bin/qa-extended.sh search paths
- .claude/settings.local.json permission paths

Workflow: .agents/runs/CORE-LIB-RENAME-001/ (Analyst → Planner →
Executor → Code Review (4 findings fixed) → Security Review →
Acceptance Test → Finalizer)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

core/Service/Settings/SettingsUserLifecycleGateway.php

@@ -0,0 +1,80 @@
+<?php
+
+namespace MintyPHP\Service\Settings;
+
+class SettingsUserLifecycleGateway
+{
+    private const USER_INACTIVITY_DEACTIVATE_DAYS_FALLBACK = 180;
+    private const USER_INACTIVITY_DELETE_DAYS_FALLBACK = 365;
+    private const USER_INACTIVITY_DAYS_MIN = 0;
+    private const USER_INACTIVITY_DAYS_MAX = 3650;
+
+    public function __construct(private readonly SettingsMetadataGateway $settingsMetadataGateway)
+    {
+    }
+
+    public function getUserInactivityDeactivateDays(): int
+    {
+        $value = $this->settingsMetadataGateway->getInt(SettingKeys::USER_INACTIVITY_DEACTIVATE_DAYS_KEY);
+        if ($value !== null && $this->isValidInactivityDays($value)) {
+            return $value;
+        }
+
+        return self::USER_INACTIVITY_DEACTIVATE_DAYS_FALLBACK;
+    }
+
+    public function setUserInactivityDeactivateDays(?int $days, ?string $description = null): bool
+    {
+        $value = $days ?? self::USER_INACTIVITY_DEACTIVATE_DAYS_FALLBACK;
+        if (!$this->isValidInactivityDays($value)) {
+            return false;
+        }
+        if ($value === 0) {
+            $deleteUpdated = $this->settingsMetadataGateway->set(
+                SettingKeys::USER_INACTIVITY_DELETE_DAYS_KEY,
+                '0',
+                'setting.user_inactivity_delete_days'
+            );
+            if (!$deleteUpdated) {
+                return false;
+            }
+        }
+
+        $desc = $description ?? 'setting.user_inactivity_deactivate_days';
+        return $this->settingsMetadataGateway->set(SettingKeys::USER_INACTIVITY_DEACTIVATE_DAYS_KEY, (string) $value, $desc);
+    }
+
+    public function getUserInactivityDeleteDays(): int
+    {
+        $deactivateDays = $this->getUserInactivityDeactivateDays();
+        if ($deactivateDays <= 0) {
+            return 0;
+        }
+
+        $value = $this->settingsMetadataGateway->getInt(SettingKeys::USER_INACTIVITY_DELETE_DAYS_KEY);
+        if ($value !== null && $this->isValidInactivityDays($value)) {
+            return $value;
+        }
+
+        return self::USER_INACTIVITY_DELETE_DAYS_FALLBACK;
+    }
+
+    public function setUserInactivityDeleteDays(?int $days, ?string $description = null): bool
+    {
+        $value = $days ?? self::USER_INACTIVITY_DELETE_DAYS_FALLBACK;
+        if (!$this->isValidInactivityDays($value)) {
+            return false;
+        }
+        if ($value > 0 && $this->getUserInactivityDeactivateDays() <= 0) {
+            return false;
+        }
+
+        $desc = $description ?? 'setting.user_inactivity_delete_days';
+        return $this->settingsMetadataGateway->set(SettingKeys::USER_INACTIVITY_DELETE_DAYS_KEY, (string) $value, $desc);
+    }
+
+    private function isValidInactivityDays(int $days): bool
+    {
+        return $days >= self::USER_INACTIVITY_DAYS_MIN && $days <= self::USER_INACTIVITY_DAYS_MAX;
+    }
+}