Implement ID-based routing and folder auto-generation from titles

Major features:
- Switch from slug-based to ID-based routing (/documents/123)
- Enable title editing with automatic slug/path regeneration
- Auto-generate folder structure from title slashes (e.g., Laravel/Livewire/Components)
- Persist sidebar folder open/close state using localStorage
- Remove slug unique constraint (ID routing makes it unnecessary)
- Implement recursive tree view with multi-level folder support

Architecture changes:
- DocumentService: Add generatePathAndSlug() for title-based path generation
- Routes: Change from {document:slug} to {document} for ID binding
- SidebarTree: Extract recursive rendering to partials/tree-item.blade.php
- Database: Remove unique constraint from documents.slug column

UI improvements:
- Display only last path component in sidebar (Components vs Laravel/Livewire/Components)
- Folder state persists across page navigation via localStorage
- Title field accepts slashes for folder organization

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

docker/nginx/default.conf

@@ -0,0 +1,36 @@
+server {
+    listen 80;
+    server_name localhost;
+    root /var/www/html/public;
+
+    index index.php index.html index.htm;
+
+    charset utf-8;
+
+    location / {
+        try_files $uri $uri/ /index.php?$query_string;
+    }
+
+    location = /favicon.ico { access_log off; log_not_found off; }
+    location = /robots.txt  { access_log off; log_not_found off; }
+
+    error_page 404 /index.php;
+
+    location ~ \.php$ {
+        fastcgi_pass php:9000;
+        fastcgi_index index.php;
+        fastcgi_param SCRIPT_FILENAME $realpath_root$fastcgi_script_name;
+        include fastcgi_params;
+        fastcgi_hide_header X-Powered-By;
+    }
+
+    location ~ /\.(?!well-known).* {
+        deny all;
+    }
+
+    # キャッシュ設定
+    location ~* \.(jpg|jpeg|png|gif|ico|css|js|svg|woff|woff2|ttf|eot)$ {
+        expires 30d;
+        add_header Cache-Control "public, immutable";
+    }
+}