chore(v5): archive V5 implementation and remove runtime integration

Move V5 source, migrations, UI, scripts, and tests into documentation, then remove V5 routes, models, jobs, configuration, dependencies, and application hooks.

app/Http/Middleware/V5/EnsureCurrentTeam.php

@@ -1,58 +0,0 @@
-<?php
-
-namespace App\Http\Middleware\V5;
-
-use App\Models\Team;
-use App\Models\User;
-use Closure;
-use Illuminate\Http\Request;
-use Symfony\Component\HttpFoundation\Response;
-
-class EnsureCurrentTeam
-{
-    public function handle(Request $request, Closure $next): Response
-    {
-        /** @var User|null $user */
-        $user = $request->user();
-
-        if (! $user) {
-            return $next($request);
-        }
-
-        $currentTeam = $this->resolveCurrentTeam($user);
-
-        if (! $currentTeam) {
-            abort(403, 'No team available for this user.');
-        }
-
-        // The v4 UI stores a full Team model under the same session key and
-        // reads arbitrary columns off it, so only rewrite the session when the
-        // resolved team actually changed — and always store the full model.
-        if (data_get(session('currentTeam'), 'id') !== $currentTeam->id) {
-            session(['currentTeam' => $currentTeam]);
-        }
-
-        $request->attributes->set('v5.currentTeam', $currentTeam);
-
-        return $next($request);
-    }
-
-    private function resolveCurrentTeam(User $user): ?Team
-    {
-        $sessionTeamId = data_get(session('currentTeam'), 'id');
-
-        if ($sessionTeamId) {
-            $sessionTeam = $user->teams()
-                ->whereKey($sessionTeamId)
-                ->first();
-
-            if ($sessionTeam) {
-                return $sessionTeam;
-            }
-        }
-
-        return $user->teams()
-            ->orderBy('teams.id')
-            ->first();
-    }
-}

app/Http/Middleware/V5/HandleInertiaRequests.php

@@ -1,28 +0,0 @@
-<?php
-
-namespace App\Http\Middleware\V5;
-
-use Illuminate\Http\Request;
-use Inertia\Middleware;
-
-class HandleInertiaRequests extends Middleware
-{
-    protected $rootView = 'v5.app';
-
-    public function share(Request $request): array
-    {
-        return [
-            ...parent::share($request),
-            'auth' => [
-                'user' => $request->user() ? [
-                    'id' => $request->user()->id,
-                    'name' => $request->user()->name,
-                    'email' => $request->user()->email,
-                ] : null,
-            ],
-            'currentTeam' => $request->attributes->get('v5.currentTeam') ? [
-                'id' => $request->attributes->get('v5.currentTeam')->id,
-            ] : null,
-        ];
-    }
-}