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/SmartLink/Api/CreateSmartLink.php

@@ -0,0 +1,58 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Application\SmartLink\Api;
+
+use App\Domain\SmartLink\Enums\LinkType;
+use App\Domain\SmartLink\Services\SmartLinkService;
+use App\Domain\SmartLink\ValueObjects\LinkTitle;
+use App\Framework\Attributes\Route;
+use App\Framework\Http\HttpRequest;
+use App\Framework\Http\Method;
+use App\Framework\Http\Status;
+use App\Framework\Router\Result\JsonResult;
+
+final readonly class CreateSmartLink
+{
+    public function __construct(
+        private SmartLinkService $smartLinkService
+    ) {}
+
+    #[Route(path: '/api/smart-links', method: Method::POST)]
+    public function __invoke(HttpRequest $request): JsonResult
+    {
+        $data = $request->parsedBody->toArray();
+
+        // Workaround: If parsedBody is empty, try parsing JSON directly
+        if (empty($data)) {
+            $rawBody = file_get_contents('php://input');
+            $data = json_decode($rawBody, true) ?? [];
+        }
+
+        if (!isset($data['type']) || !isset($data['title'])) {
+            return new JsonResult([
+                'error' => 'Missing required fields: type and title'
+            ], Status::BAD_REQUEST);
+        }
+
+        $type = LinkType::from($data['type'] ?? '');
+        $title = LinkTitle::fromString($data['title'] ?? '');
+
+        $smartLink = $this->smartLinkService->createLink(
+            type: $type,
+            title: $title,
+            userId: $data['user_id'] ?? null,
+            coverImageUrl: $data['cover_image_url'] ?? null
+        );
+
+        return new JsonResult([
+            'id' => $smartLink->id->toString(),
+            'short_code' => $smartLink->shortCode->toString(),
+            'type' => $smartLink->type->value,
+            'title' => $smartLink->title->toString(),
+            'status' => $smartLink->status->value,
+            'created_at' => $smartLink->createdAt->format('Y-m-d H:i:s')
+        ], Status::CREATED);
+    }
+}