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/Data/GridUserCountEnricher.php

@@ -0,0 +1,46 @@
+<?php
+
+namespace MintyPHP\Service\Data;
+
+class GridUserCountEnricher
+{
+    /**
+     * Collect entity IDs from grid rows, batch-query total and active user
+     * counts, and return a lookup map keyed by entity ID.
+     *
+     * @param array[]                        $rows        Grid result rows (each must have an 'id' key).
+     * @param callable(list<int>): array<int,int> $countTotal  fn(ids) => [entityId => totalCount]
+     * @param callable(list<int>): array<int,int> $countActive fn(ids) => [entityId => activeCount]
+     * @return array<int, array{active_users: int, inactive_users: int}>
+     */
+    public function computeCounts(array $rows, callable $countTotal, callable $countActive): array
+    {
+        $ids = [];
+        foreach ($rows as $row) {
+            $id = (int) ($row['id'] ?? 0);
+            if ($id > 0) {
+                $ids[] = $id;
+            }
+        }
+        $ids = array_values(array_unique($ids));
+
+        if (!$ids) {
+            return [];
+        }
+
+        $totalCounts = $countTotal($ids);
+        $activeCounts = $countActive($ids);
+
+        $result = [];
+        foreach ($ids as $id) {
+            $total = (int) ($totalCounts[$id] ?? 0);
+            $active = (int) ($activeCounts[$id] ?? 0);
+            $result[$id] = [
+                'active_users' => $active,
+                'inactive_users' => max(0, $total - $active),
+            ];
+        }
+
+        return $result;
+    }
+}