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/ValueObjects/NavigationSection.php

@@ -0,0 +1,63 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Application\Admin\ValueObjects;
+
+final readonly class NavigationSection
+{
+    /** @param array<NavigationItem> $items */
+    public function __construct(
+        public string $name,
+        public array $items,
+        public ?string $icon = null
+    ) {
+    }
+
+    public static function fromArray(array $data): self
+    {
+        $items = [];
+        foreach ($data['items'] ?? [] as $itemData) {
+            $items[] = NavigationItem::fromArray($itemData);
+        }
+
+        return new self(
+            name: $data['section'] ?? $data['name'] ?? '',
+            items: $items,
+            icon: $data['icon'] ?? null
+        );
+    }
+
+    public function toArray(): array
+    {
+        return [
+            'section' => $this->name,
+            'name' => $this->name,
+            'items' => array_map(
+                fn (NavigationItem $item) => $item->toArray(),
+                $this->items
+            ),
+            'icon' => $this->icon,
+        ];
+    }
+
+    public function addItem(NavigationItem $item): self
+    {
+        return new self(
+            name: $this->name,
+            items: [...$this->items, $item],
+            icon: $this->icon
+        );
+    }
+
+    public function hasActiveItem(string $currentPath): bool
+    {
+        foreach ($this->items as $item) {
+            if ($item->isActive($currentPath)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+}