docs: consolidate documentation into organized structure

- Move 12 markdown files from root to docs/ subdirectories
- Organize documentation by category:
  • docs/troubleshooting/ (1 file)  - Technical troubleshooting guides
  • docs/deployment/      (4 files) - Deployment and security documentation
  • docs/guides/          (3 files) - Feature-specific guides
  • docs/planning/        (4 files) - Planning and improvement proposals

Root directory cleanup:
- Reduced from 16 to 4 markdown files in root
- Only essential project files remain:
  • CLAUDE.md (AI instructions)
  • README.md (Main project readme)
  • CLEANUP_PLAN.md (Current cleanup plan)
  • SRC_STRUCTURE_IMPROVEMENTS.md (Structure improvements)

This improves:
✅ Documentation discoverability
✅ Logical organization by purpose
✅ Clean root directory
✅ Better maintainability

src/Application/Admin/System/PhpInfoController.php

@@ -0,0 +1,65 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Application\Admin\System;
+
+use App\Application\Admin\Service\AdminLayoutProcessor;
+use App\Application\Admin\System\Service\PhpInfoService;
+use App\Framework\Attributes\Route;
+use App\Framework\Auth\Auth;
+use App\Framework\DateTime\Clock;
+use App\Framework\Http\Method;
+use App\Framework\Meta\MetaData;
+use App\Framework\Router\Result\ViewResult;
+
+final readonly class PhpInfoController
+{
+    public function __construct(
+        private PhpInfoService $phpInfoService,
+        private AdminLayoutProcessor $layoutProcessor,
+        private Clock $clock,
+    ) {
+    }
+
+    #[Auth]
+    #[Route(path: '/admin/system/phpinfo', method: Method::GET, name: 'admin.system.phpinfo')]
+    public function show(): ViewResult
+    {
+        $phpInfo = $this->phpInfoService->getStructuredInfo();
+
+        // Prepare data for template
+        $generalInfo = [];
+        foreach ($phpInfo['general'] as $key => $value) {
+            $generalInfo[] = [
+                'key' => ucwords(str_replace('_', ' ', $key)),
+                'value' => (string)$value,
+            ];
+        }
+
+        $configInfo = [];
+        foreach ($phpInfo['configuration'] as $key => $value) {
+            $configInfo[] = [
+                'key' => ucwords(str_replace('_', ' ', $key)),
+                'value' => (string)$value,
+            ];
+        }
+
+        $data = [
+            'title' => 'PHP Information',
+            'general_info' => $generalInfo,
+            'config_info' => $configInfo,
+            'extensions_count' => $phpInfo['extensions']['count'],
+            'extensions_list' => $phpInfo['extensions']['list'],
+            'current_year' => $this->clock->now()->format('Y'),
+        ];
+
+        $finalData = $this->layoutProcessor->processLayoutFromArray($data);
+
+        return new ViewResult(
+            template: 'phpinfo',
+            metaData: new MetaData('PHP Information', 'PHP Information and Configuration'),
+            data: $finalData
+        );
+    }
+}