Add Filament admin panel and creative public portfolio site

Adds a Filament admin (Profile settings page plus CRUD resources for
Education, Experience, Projects, and Posts) backing a public-facing
personal site: hero/about/timeline home page, project showcase, and
blog, styled with a dark editorial theme (Fraunces + Instrument Sans).

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

app/Models/Post.php

@@ -0,0 +1,51 @@
+<?php
+
+namespace App\Models;
+
+use Illuminate\Database\Eloquent\Builder;
+use Illuminate\Database\Eloquent\Casts\Attribute;
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Support\Facades\Storage;
+use Illuminate\Support\Str;
+
+class Post extends Model
+{
+    protected $fillable = [
+        'title',
+        'slug',
+        'excerpt',
+        'body',
+        'cover_image',
+        'tags',
+        'published_at',
+    ];
+
+    protected $casts = [
+        'tags' => 'array',
+        'published_at' => 'datetime',
+    ];
+
+    protected static function booted(): void
+    {
+        static::saving(function (Post $post) {
+            if (blank($post->slug)) {
+                $post->slug = Str::slug($post->title);
+            }
+        });
+    }
+
+    public function scopePublished(Builder $query): Builder
+    {
+        return $query->whereNotNull('published_at')->where('published_at', '<=', now());
+    }
+
+    public function getRouteKeyName(): string
+    {
+        return 'slug';
+    }
+
+    protected function coverImageUrl(): Attribute
+    {
+        return Attribute::get(fn () => $this->cover_image ? Storage::disk('public')->url($this->cover_image) : null);
+    }
+}